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android / platform / external / toybox / 6d28316864a44ea16669de79f2aefab2933fbf3a / . / toys / pending / sh.c
blob: 5379198ae1e434d87f58bfa56cba12242f6ee0c7 [file] [log] [blame]
/* sh.c - toybox shell
*
* Copyright 2006 Rob Landley <rob@landley.net>
*
* This shell aims for bash compatibility. The bash man page is at:
* http://man7.org/linux/man-pages/man1/bash.1.html
*
* The POSIX-2008/SUSv4 shell spec is at:
* http://opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html
* and http://opengroup.org/onlinepubs/9699919799/utilities/sh.html
*
* deviations from posix: don't care about $LANG or $LC_ALL
* builtins: alias bg command fc fg getopts jobs newgrp read umask unalias wait
* disown suspend source pushd popd dirs logout times trap cd hash exit
* unset local export readonly set : . let history declare ulimit type
* "special" builtins: break continue eval exec return shift
* external with extra shell behavior: kill pwd time test
* * ? [ # ~ = % [[ ]] function select exit label:
* TODO: case, wildcard +(*|?), job control (find_plus_minus), ${x//}, $(())
* TODO: support case in $() because $(case a in a) ;; ; esac) stops at first )
* TODO: test exit from "trap EXIT" doesn't recurse
* TODO: ! history expansion
* TODO: getuid() vs geteuid()
* TODO: test that $PS1 color changes work without stupid \[ \] hack
* TODO: Handle embedded NUL bytes in the command line? (When/how?)
* TODO: set -e -u -o pipefail, shopt -s nullglob
*
* bash man page:
* control operators || & && ; ;; ;& ;;& ( ) | |& <newline>
* reserved words
* ! case coproc do done elif else esac fi for function if in select
* then until while { } time [[ ]]
*
* Flow control statements:
*
* if/then/elif/else/fi, for select while until/do/done, case/esac,
* {/}, [[/]], (/), function assignment
USE_SH(NEWTOY(cd, ">1LP[-LP]", TOYFLAG_NOFORK))
USE_SH(NEWTOY(declare, "pAailunxr", TOYFLAG_NOFORK))
// TODO tpgfF
USE_SH(NEWTOY(eval, 0, TOYFLAG_NOFORK))
USE_SH(NEWTOY(exec, "^cla:", TOYFLAG_NOFORK))
USE_SH(NEWTOY(exit, 0, TOYFLAG_NOFORK))
USE_SH(NEWTOY(export, "np", TOYFLAG_NOFORK))
USE_SH(NEWTOY(jobs, "lnprs", TOYFLAG_NOFORK))
USE_SH(NEWTOY(set, 0, TOYFLAG_NOFORK))
USE_SH(NEWTOY(shift, ">1", TOYFLAG_NOFORK))
USE_SH(NEWTOY(source, "<1", TOYFLAG_NOFORK))
USE_SH(OLDTOY(., source, TOYFLAG_NOFORK))
USE_SH(NEWTOY(unset, "fvn[!fv]", TOYFLAG_NOFORK))
USE_SH(NEWTOY(wait, "n", TOYFLAG_NOFORK))
USE_SH(NEWTOY(sh, "0(noediting)(noprofile)(norc)sc:i", TOYFLAG_BIN))
USE_SH(OLDTOY(toysh, sh, TOYFLAG_BIN))
USE_SH(OLDTOY(bash, sh, TOYFLAG_BIN))
// Login lies in argv[0], so add some aliases to catch that
USE_SH(OLDTOY(-sh, sh, 0))
USE_SH(OLDTOY(-toysh, sh, 0))
USE_SH(OLDTOY(-bash, sh, 0))
config SH
bool "sh (toysh)"
default n
help
usage: sh [-c command] [script]
Command shell. Runs a shell script, or reads input interactively
and responds to it.
-c command line to execute
-i interactive mode (default when STDIN is a tty)
# These are here for the help text, they're not selectable and control nothing
config CD
bool
default n
depends on SH
help
usage: cd [-PL] [-] [path]
Change current directory. With no arguments, go $HOME. Sets $OLDPWD to
previous directory: cd - to return to $OLDPWD.
-P Physical path: resolve symlinks in path
-L Local path: .. trims directories off $PWD (default)
config DECLARE
bool
default n
depends on SH
help
usage: declare [-pAailunxr] [NAME...]
Set or print variable attributes and values.
-p Print variables instead of setting
-A Associative array
-a Indexed array
-i Integer
-l Lower case
-n Name reference (symlink)
-r Readonly
-u Uppercase
-x Export
config EXIT
bool
default n
depends on SH
help
usage: exit [status]
Exit shell. If no return value supplied on command line, use value
of most recent command, or 0 if none.
config SET
bool
default n
depends on SH
help
usage: set [+a] [+o OPTION] [VAR...]
Set variables and shell attributes. Use + to disable and - to enable.
NAME=VALUE arguments assign to the variable, any leftovers set $1, $2...
With no arguments, prints current variables.
-f NAME is a function
-v NAME is a variable
-n don't follow name reference
OPTIONs:
history - enable command history
config UNSET
bool
default n
depends on SH
help
usage: unset [-fvn] NAME...
-f NAME is a function
-v NAME is a variable
-n dereference NAME and unset that
config EVAL
bool
default n
depends on SH
help
usage: eval COMMAND...
Execute (combined) arguments as a shell command.
config EXEC
bool
default n
depends on SH
help
usage: exec [-cl] [-a NAME] COMMAND...
-a set argv[0] to NAME
-c clear environment
-l prepend - to argv[0]
config EXPORT
bool
default n
depends on SH
help
usage: export [-n] [NAME[=VALUE]...]
Make variables available to child processes. NAME exports existing local
variable(s), NAME=VALUE sets and exports.
-n Unexport. Turn listed variable(s) into local variables.
With no arguments list exported variables/attributes as "declare" statements.
config JOBS
bool
default n
depends on SH
help
usage: jobs [-lnprs] [%JOB | -x COMMAND...]
List running/stopped background jobs.
-l Include process ID in list
-n Show only new/changed processes
-p Show process IDs only
-r Show running processes
-s Show stopped processes
config LOCAL
bool
default n
depends on SH
help
usage: local [NAME[=VALUE]...]
Create a local variable that lasts until return from this function.
With no arguments lists local variables in current function context.
TODO: implement "declare" options.
config SHIFT
bool
default n
depends on SH
help
usage: shift [N]
Skip N (default 1) positional parameters, moving $1 and friends along the list.
Does not affect $0.
config SOURCE
bool
default n
depends on SH
help
usage: source FILE [ARGS...]
Read FILE and execute commands. Any ARGS become positional parameters.
config WAIT
bool
default n
depends on SH
help
usage: wait [-n] [ID...]
Wait for background processes to exit, returning its exit code.
ID can be PID or job, with no IDs waits for all backgrounded processes.
-n Wait for next process to exit
*/
#define FOR_sh
#include "toys.h"
GLOBALS(
union {
struct {
char *c;
} sh;
struct {
char *a;
} exec;
};
// keep SECONDS here: used to work around compiler limitation in run_command()
long long SECONDS;
char *isexec, *wcpat;
unsigned options, jobcnt, LINENO;
int hfd, pid, bangpid, srclvl, recursion;
// Callable function array
struct sh_function {
char *name;
struct sh_pipeline { // pipeline segments: linked list of arg w/metadata
struct sh_pipeline *next, *prev, *end;
int count, here, type, lineno;
struct sh_arg {
char **v;
int c;
} arg[1];
} *pipeline;
unsigned long refcount;
} **functions;
long funcslen;
// runtime function call stack
struct sh_fcall {
struct sh_fcall *next, *prev;
// This dlist in reverse order: TT.ff current function, TT.ff->prev globals
struct sh_vars {
long flags;
char *str;
} *vars;
long varslen, varscap, shift, oldlineno;
struct sh_function *func; // TODO wire this up
struct sh_pipeline *pl;
char *ifs, *omnom;
struct sh_arg arg;
struct arg_list *delete;
// Runtime stack of nested if/else/fi and for/do/done contexts.
struct sh_blockstack {
struct sh_blockstack *next;
struct sh_pipeline *start, *middle;
struct sh_process *pp; // list of processes piping in to us
int run, loop, *urd, pout, pipe;
struct sh_arg farg; // for/select arg stack, case wildcard deck
struct arg_list *fdelete; // farg's cleanup list
char *fvar; // for/select's iteration variable name
} *blk;
} *ff;
// TODO ctrl-Z suspend should stop script
struct sh_process {
struct sh_process *next, *prev; // | && ||
struct arg_list *delete; // expanded strings
// undo redirects, a=b at start, child PID, exit status, has !, job #
int *urd, envlen, pid, exit, flags, job, dash;
long long when; // when job backgrounded/suspended
struct sh_arg *raw, arg;
} *pp; // currently running process
// job list, command line for $*, scratch space for do_wildcard_files()
struct sh_arg jobs, *wcdeck;
)
// Prototype because $($($(blah))) nests, leading to run->parse->run loop
int do_source(char *name, FILE *ff);
// ordered for greedy matching, so >&; becomes >& ; not > &;
// making these const means I need to typecast the const away later to
// avoid endless warnings.
static const char *redirectors[] = {"<<<", "<<-", "<<", "<&", "<>", "<", ">>",
">&", ">|", ">", "&>>", "&>", 0};
// The order of these has to match the string in set_main()
#define OPT_B 0x100
#define OPT_C 0x200
#define OPT_x 0x400
// only export $PWD and $OLDPWD on first cd
#define OPT_cd 0x80000000
// struct sh_process->flags
#define PFLAG_NOT 1
static void syntax_err(char *s)
{
struct sh_fcall *ff = TT.ff;
// TODO: script@line only for script not interactive.
for (ff = TT.ff; ff != TT.ff->prev; ff = ff->next) if (ff->omnom) break;
error_msg("syntax error '%s'@%u: %s", ff->omnom ? : "-c", TT.LINENO, s);
toys.exitval = 2;
if (!(TT.options&FLAG_i)) xexit();
}
void debug_show_fds()
{
int x = 0, fd = open("/proc/self/fd", O_RDONLY);
DIR *X = fdopendir(fd);
struct dirent *DE;
char *s, *ss = 0, buf[4096], *sss = buf;
if (!X) return;
for (; (DE = readdir(X));) {
if (atoi(DE->d_name) == fd) continue;
s = xreadlink(ss = xmprintf("/proc/self/fd/%s", DE->d_name));
if (s && *s != '.') sss += sprintf(sss, ", %s=%s"+2*!x++, DE->d_name, s);
free(s); free(ss);
}
*sss = 0;
dprintf(2, "%d fd:%s\n", getpid(), buf);
closedir(X);
}
// append to array with null terminator and realloc as necessary
static void arg_add(struct sh_arg *arg, char *data)
{
// expand with stride 32. Micro-optimization: don't realloc empty stack
if (!(arg->c&31) && (arg->c || !arg->v))
arg->v = xrealloc(arg->v, sizeof(char *)*(arg->c+33));
arg->v[arg->c++] = data;
arg->v[arg->c] = 0;
}
// add argument to an arg_list
static void *push_arg(struct arg_list **list, void *arg)
{
struct arg_list *al;
if (list) {
al = xmalloc(sizeof(struct arg_list));
al->next = *list;
al->arg = arg;
*list = al;
}
return arg;
}
static void arg_add_del(struct sh_arg *arg, char *data,struct arg_list **delete)
{
arg_add(arg, push_arg(delete, data));
}
// Assign one variable from malloced key=val string, returns var struct
// TODO implement remaining types
#define VAR_NOFREE (1<<10)
#define VAR_WHITEOUT (1<<9)
#define VAR_DICT (1<<8)
#define VAR_ARRAY (1<<7)
#define VAR_INT (1<<6)
#define VAR_TOLOWER (1<<5)
#define VAR_TOUPPER (1<<4)
#define VAR_NAMEREF (1<<3)
#define VAR_EXPORT (1<<2)
#define VAR_READONLY (1<<1)
#define VAR_MAGIC (1<<0)
// return length of valid variable name
static char *varend(char *s)
{
if (isdigit(*s)) return s;
while (*s>' ' && (*s=='_' || !ispunct(*s))) s++;
return s;
}
// TODO: this has to handle VAR_NAMEREF, but return dangling symlink
// Also, unset -n, also "local ISLINK" to parent var.
// Return sh_vars * or 0 if not found.
// Sets *pff to function (only if found), only returns whiteouts if pff not NULL
static struct sh_vars *findvar(char *name, struct sh_fcall **pff)
{
int len = varend(name)-name;
struct sh_fcall *ff = TT.ff;
// advance through locals to global context, ignoring whiteouts
if (len) do {
struct sh_vars *var = ff->vars+ff->varslen;
if (var) while (var--!=ff->vars) {
if (strncmp(var->str, name, len) || var->str[len]!='=') continue;
if (pff) *pff = ff;
else if (var->flags&VAR_WHITEOUT) return 0;
return var;
}
} while ((ff = ff->next)!=TT.ff);
return 0;
}
// Append variable to ff->vars, returning *struct. Does not check duplicates.
static struct sh_vars *addvar(char *s, struct sh_fcall *ff)
{
if (ff->varslen == ff->varscap && !(ff->varslen&31)) {
ff->varscap += 32;
ff->vars = xrealloc(ff->vars, (ff->varscap)*sizeof(*ff->vars));
}
if (!s) return ff->vars;
ff->vars[ff->varslen].flags = 0;
ff->vars[ff->varslen].str = s;
return ff->vars+ff->varslen++;
}
static char **nospace(char **ss)
{
while (isspace(**ss)) ++*ss;
return ss;
}
/*
15L ( [ . -> ++ --
14R (all prefix operators)
++ -- + - ! ~ (typecast) * & sizeof
13L * / %
12L + -
11L << >>
10L < <= > >=
9L == !=
8L & (bitwise)
7L ^ (xor)
6L |
5L &&
4L ||
3R ? :
2R (assignments) = += -= *= /= %= &= ^= |= <<= >>=
1L ,
*/
// Recursively calculate string into dd, returns 0 if failed, ss = error point
static int recalculate(long long *dd, char **ss, int lvl)
{
long long ee, ff;
char cc = **nospace(ss);
// TODO: assignable (variable)
// Always start handling unary prefixes, parenthetical blocks, and constants
if (cc=='+' || cc=='-') {
++*ss;
if (!recalculate(dd, ss, 1)) return 0;
if (cc=='-') *dd = -*dd;
} else if (cc=='(') {
++*ss;
if (!recalculate(dd, ss, 1)) return 0;
if (**ss!=')') return 0;
else ++*ss;
} else if (isdigit(cc)) *dd = strtoll(*ss, ss, 0); //TODO overflow?
else if (!lvl && (!cc || cc==')')) {
*dd = 0;
return 1;
} else return 0;
// x^y binds first
if (lvl<4) while (strstart(nospace(ss), "**")) {
if (!recalculate(&ee, ss, 4)) return 0;
if (ee<0) perror_msg("** < 0");
for (ff = *dd, *dd = 1; ee; ee--) *dd *= ff;
}
// w*x/y%z bind next
if (lvl<3) while ((cc = **nospace(ss))) {
if (cc=='*' || cc=='/' || cc=='%') {
++*ss;
if (!recalculate(&ee, ss, 3)) return 0;
if (cc=='*') *dd *= ee;
else if (cc=='%') *dd %= ee;
else if (!ee) {
perror_msg("/0");
return 0;
} else *dd /= ee;
} else break;
}
// x+y-z
if (lvl<2) while ((cc = **nospace(ss))) {
if (cc=='+' || cc=='-') {
++*ss;
if (!recalculate(&ee, ss, 2)) return 0;
if (cc=='+') *dd += ee;
else *dd -= ee;
} else break;
}
nospace(ss);
return 1;
}
static int calculate(long long *ll, char *equation)
{
char *ss = equation;
// TODO: error_msg->sherror_msg() with LINENO for scripts
if (!recalculate(ll, &ss, 0) || *ss) {
perror_msg("bad math: %s @ %d", equation, (int)(ss-equation));
return 0;
}
return 1;
}
// Return length of utf8 char @s fitting in len, writing value into *cc
int getutf8(char *s, int len, int *cc)
{
unsigned wc;
if (len<0) wc = len = 0;
else if (1>(len = utf8towc(&wc, s, len))) wc = *s, len = 1;
if (cc) *cc = wc;
return len;
}
// get value of variable starting at s.
static char *getvar(char *s)
{
struct sh_vars *var = findvar(s, 0);
if (!var) return 0;
if (var->flags & VAR_MAGIC) {
char c = *var->str;
if (c == 'S') sprintf(toybuf, "%lld", (millitime()-TT.SECONDS)/1000);
else if (c == 'R') sprintf(toybuf, "%ld", random()&((1<<16)-1));
else if (c == 'L') sprintf(toybuf, "%u", TT.ff->pl->lineno);
else if (c == 'G') sprintf(toybuf, "TODO: GROUPS");
else if (c == 'B') sprintf(toybuf, "%d", getpid());
else if (c == 'E') {
struct timespec ts;
clock_gettime(CLOCK_REALTIME, &ts);
sprintf(toybuf, "%lld%c%06ld", (long long)ts.tv_sec, (s[5]=='R')*'.',
ts.tv_nsec/1000);
}
return toybuf;
}
return varend(var->str)+1;
}
// Update $IFS cache in function call stack after variable assignment
static void cache_ifs(char *s, struct sh_fcall *ff)
{
if (!strncmp(s, "IFS=", 4))
do ff->ifs = s+4; while ((ff = ff->next) != TT.ff->prev);
}
// declare -aAilnrux
// ft
// TODO VAR_ARRAY VAR_DICT
// Assign new name=value string for existing variable. s takes x=y or x+=y
static struct sh_vars *setvar_found(char *s, int freeable, struct sh_vars *var)
{
char *ss, *sss, *sd, buf[24];
long ii, jj, kk, flags = var->flags&~VAR_WHITEOUT;
long long ll;
int cc, vlen = varend(s)-s;
if (flags&VAR_READONLY) {
error_msg("%.*s: read only", vlen, s);
goto bad;
}
// If += has no old value (addvar placeholder or empty old var) yank the +
if (s[vlen]=='+' && (var->str==s || !strchr(var->str, '=')[1])) {
ss = xmprintf("%.*s%s", vlen, s, s+vlen+1);
if (var->str==s) {
if (!freeable++) var->flags |= VAR_NOFREE;
} else if (freeable++) free(s);
s = ss;
}
// Handle VAR_NAMEREF mismatch by replacing name
if (strncmp(var->str, s, vlen)) {
ss = s+vlen+(s[vlen]=='+')+1;
ss = xmprintf("%.*s%s", (vlen = varend(var->str)-var->str)+1, var->str, ss);
if (freeable++) free(s);
s = ss;
}
// utf8 aware case conversion, two pass (measure, allocate, convert) because
// unicode IS stupid enough for upper/lower case to be different utf8 byte
// lengths, for example lowercase of U+023a (c8 ba) is U+2c65 (e2 b1 a5)
if (flags&(VAR_TOUPPER|VAR_TOLOWER)) {
for (jj = kk = 0, sss = 0; jj<2; jj++, sss = sd = xmalloc(vlen+kk+2)) {
sd = jj ? stpncpy(sss, s, vlen+1) : (void *)&sss;
for (ss = s+vlen+1; (ii = getutf8(ss, 4, &cc)); ss += ii) {
kk += wctoutf8(sd, (flags&VAR_TOUPPER) ? towupper(cc) : towlower(cc));
if (jj) {
sd += kk;
kk = 0;
}
}
}
*sd = 0;
if (freeable++) free(s);
s = sss;
}
// integer variables treat += differently
ss = s+vlen+(s[vlen]=='+')+1;
if (flags&VAR_INT) {
if (!calculate(&ll, ss)) goto bad;
sprintf(buf, "%lld", ll);
if (flags&VAR_MAGIC) {
if (*s == 'S') {
ll *= 1000;
TT.SECONDS = (s[vlen]=='+') ? TT.SECONDS+ll : millitime()-ll;
} else if (*s == 'R') srandom(ll);
if (freeable) free(s);
// magic can't be whiteout or nofree, and keeps old string
return var;
} else if (s[vlen]=='+' || strcmp(buf, ss)) {
if (s[vlen]=='+') ll += atoll(strchr(var->str, '=')+1);
ss = xmprintf("%.*s=%lld", vlen, s, ll);
if (freeable++) free(s);
s = ss;
}
} else if (s[vlen]=='+' && !(flags&VAR_MAGIC)) {
ss = xmprintf("%s%s", var->str, ss);
if (freeable++) free(s);
s = ss;
}
// Replace old string with new one, adjusting nofree status
if (flags&VAR_NOFREE) flags ^= VAR_NOFREE;
else free(var->str);
if (!freeable) flags |= VAR_NOFREE;
var->str = s;
var->flags = flags;
return var;
bad:
if (freeable) free(s);
return 0;
}
// Creates new variables (local or global) and handles +=
// returns 0 on error, else sh_vars of new entry.
static struct sh_vars *setvar_long(char *s, int freeable, struct sh_fcall *ff)
{
struct sh_vars *vv = 0, *was;
char *ss;
if (!s) return 0;
ss = varend(s);
if (ss[*ss=='+']!='=') {
error_msg("bad setvar %s\n", s);
if (freeable) free(s);
return 0;
}
// Add if necessary, set value, and remove again if we added but set failed
if (!(was = vv = findvar(s, &ff))) (vv = addvar(s, ff))->flags = VAR_NOFREE;
if (!(vv = setvar_found(s, freeable, vv))) {
if (!was) memmove(vv, vv+1, sizeof(ff->vars)*(--ff->varslen-(vv-ff->vars)));
} else cache_ifs(vv->str, ff);
return vv;
}
// Set variable via a malloced "name=value" (or "name+=value") string.
// Returns sh_vars * or 0 for failure (readonly, etc)
static struct sh_vars *setvar(char *str)
{
return setvar_long(str, 0, TT.ff->prev);
}
// returns whether variable found (whiteout doesn't count)
static int unsetvar(char *name)
{
struct sh_fcall *ff;
struct sh_vars *var = findvar(name, &ff);
int len = varend(name)-name;
if (!var || (var->flags&VAR_WHITEOUT)) return 0;
if (var->flags&VAR_READONLY) error_msg("readonly %.*s", len, name);
else {
// turn local into whiteout
if (ff != TT.ff->prev) {
var->flags = VAR_WHITEOUT;
if (!(var->flags&VAR_NOFREE))
(var->str = xrealloc(var->str, len+2))[len+1] = 0;
// free from global context
} else {
if (!(var->flags&VAR_NOFREE)) free(var->str);
memmove(var, var+1, sizeof(ff->vars)*(ff->varslen-(var-ff->vars)));
}
if (!strcmp(name, "IFS"))
do ff->ifs = " \t\n"; while ((ff = ff->next) != TT.ff->prev);
}
return 1;
}
static struct sh_vars *setvarval(char *name, char *val)
{
return setvar(xmprintf("%s=%s", name, val));
}
// TODO: keep variable arrays sorted for binary search
// create array of variables visible in current function.
static struct sh_vars **visible_vars(void)
{
struct sh_arg arg;
struct sh_fcall *ff;
struct sh_vars *vv;
unsigned ii, jj, len;
arg.c = 0;
arg.v = 0;
// Find non-duplicate entries: TODO, sort and binary search
for (ff = TT.ff; ; ff = ff->next) {
if (ff->vars) for (ii = ff->varslen; ii--;) {
vv = ff->vars+ii;
len = 1+(varend(vv->str)-vv->str);
for (jj = 0; ;jj++) {
if (jj == arg.c) arg_add(&arg, (void *)vv);
else if (strncmp(arg.v[jj], vv->str, len)) continue;
break;
}
}
if (ff->next == TT.ff) break;
}
return (void *)arg.v;
}
// malloc declare -x "escaped string"
static char *declarep(struct sh_vars *var)
{
char *types = "rxnuliaA", *esc = "$\"\\`", *in, flags[16], *out = flags, *ss;
int len;
for (len = 0; types[len]; len++) if (var->flags&(2<<len)) *out++ = types[len];
if (out==flags) *out++ = '-';
*out = 0;
len = out-flags;
for (in = var->str; *in; in++) len += !!strchr(esc, *in);
len += in-var->str;
ss = xmalloc(len+15);
len = varend(var->str)-var->str;
out = ss + sprintf(ss, "declare -%s %.*s", flags, len, var->str);
if (var->flags != VAR_MAGIC) {
out = stpcpy(out, "=\"");
for (in = var->str+len+1; *in; *out++ = *in++)
if (strchr(esc, *in)) *out++ = '\\';
*out++ = '"';
}
*out = 0;
return ss;
}
// return length of match found at this point (try is null terminated array)
static int anystart(char *s, char **try)
{
char *ss = s;
while (*try) if (strstart(&s, *try++)) return s-ss;
return 0;
}
// does this entire string match one of the strings in try[]
static int anystr(char *s, char **try)
{
while (*try) if (!strcmp(s, *try++)) return 1;
return 0;
}
// return length of valid prefix that could go before redirect
static int redir_prefix(char *word)
{
char *s = word;
if (*s == '{') {
if (*(s = varend(s+1)) == '}' && s != word+1) s++;
else s = word;
} else while (isdigit(*s)) s++;
return s-word;
}
// parse next word from command line. Returns end, or 0 if need continuation
// caller eats leading spaces. early = skip one quote block (or return start)
// quote is depth of existing quote stack in toybuf (usually 0)
static char *parse_word(char *start, int early, int quote)
{
int ii, qq, qc = 0;
char *end = start, *ss;
// Handle redirections, <(), (( )) that only count at the start of word
ss = end + redir_prefix(end); // 123<<file- parses as 2 args: "123<<" "file-"
if (strstart(&ss, "<(") || strstart(&ss, ">(")) {
toybuf[quote++]=')';
end = ss;
} else if ((ii = anystart(ss, (void *)redirectors))) return ss+ii;
if (strstart(&end, "((")) toybuf[quote++] = 254;
// Loop to find end of this word
while (*end) {
// If we're stopping early and already handled a symbol...
if (early && end!=start && !quote) break;
// barf if we're near overloading quote stack (nesting ridiculously deep)
if (quote>4000) {
syntax_err("bad quote depth");
return (void *)1;
}
// Are we in a quote context?
if ((qq = quote ? toybuf[quote-1] : 0)) {
ii = *end++;
if ((qq==')' || qq>=254) && (ii=='(' || ii==')')) { // parentheses nest
if (ii=='(') qc++;
else if (qc) qc--;
else if (qq>=254) {
// (( can end with )) or retroactively become two (( if we hit one )
if (ii==')' && *end==')') quote--, end++;
else if (qq==254) return start+1;
else if (qq==255) toybuf[quote-1] = ')';
} else if (ii==')') quote--;
} else if (ii==qq) quote--; // matching end quote
else if (qq!='\'') end--, ii = 0; // single quote claims everything
if (ii) continue; // fall through for other quote types
// space and flow control chars only end word when not quoted in any way
} else {
if (isspace(*end)) break;
ss = end + anystart(end, (char *[]){";;&", ";;", ";&", ";", "||",
"|&", "|", "&&", "&", "(", ")", 0});
if (ss!=end) return (end==start) ? ss : end;
}
// start new quote context? (' not special within ")
if (strchr("'\"`"+(qq=='"'), ii = *end++)) toybuf[quote++] = ii;
// \? $() ${} $[] ?() *() +() @() !()
else {
if (ii=='\\') { // TODO why end[1] here? sh -c $'abc\\\ndef' Add test.
if (!*end || (*end=='\n' && !end[1])) return early ? end : 0;
} else if (ii=='$' && -1!=(qq = stridx("({[", *end))) {
if (strstart(&end, "((")) {
end--;
toybuf[quote++] = 255;
} else toybuf[quote++] = ")}]"[qq];
} else if (*end=='(' && strchr("?*+@!", ii)) toybuf[quote++] = ')';
else {
end--;
if (early && !quote) return end;
}
end++;
}
}
return (quote && !early) ? 0 : end;
}
// Return next available high (>=10) file descriptor
static int next_hfd()
{
int hfd;
for (; TT.hfd<=99999; TT.hfd++) if (-1 == fcntl(TT.hfd, F_GETFL)) break;
hfd = TT.hfd;
if (TT.hfd>99999) {
hfd = -1;
if (!errno) errno = EMFILE;
}
return hfd;
}
// Perform a redirect, saving displaced filehandle to a high (>10) fd
// rd is an int array: [0] = count, followed by from/to pairs to restore later.
// If from >= 0 dup from->to after saving to. If from == -1 just save to.
// if from == -2 schedule "to" to be closed by unredirect.
static int save_redirect(int **rd, int from, int to)
{
int cnt, hfd, *rr;
//dprintf(2, "%d redir %d to %d\n", getpid(), from, to);
if (from == to) return 0;
// save displaced to, copying to high (>=10) file descriptor to undo later
// except if we're saving to environment variable instead (don't undo that)
if (from>-2) {
if ((hfd = next_hfd())==-1) return 1;
if (hfd != dup2(to, hfd)) hfd = -1;
else fcntl(hfd, F_SETFD, FD_CLOEXEC);
// dup "to"
if (from >= 0 && to != dup2(from, to)) {
if (hfd >= 0) close(hfd);
return 1;
}
} else {
hfd = to;
to = -1;
}
// Append undo information to redirect list so we can restore saved hfd later.
if (!((cnt = *rd ? **rd : 0)&31)) *rd = xrealloc(*rd, (cnt+33)*2*sizeof(int));
*(rr = *rd) = ++cnt;
rr[2*cnt-1] = hfd;
rr[2*cnt] = to;
return 0;
}
// TODO: waitpid(WNOHANG) to clean up zombies and catch background& ending
static void subshell_callback(char **argv)
{
// This depends on environ having been replaced by caller
environ[1] = xmprintf("@%d,%d", getpid(), getppid());
environ[2] = xmprintf("$=%d", TT.pid);
// TODO: test $$ in (nommu)
}
// TODO what happens when you background a function?
// turn a parsed pipeline back into a string.
static char *pl2str(struct sh_pipeline *pl, int one)
{
struct sh_pipeline *end = 0, *pp;
int len QUIET, i;
char *ss;
// Find end of block (or one argument)
if (one) end = pl->next;
else for (end = pl, len = 0; end; end = end->next)
if (end->type == 1) len++;
else if (end->type == 3 && --len<0) break;
// measure, then allocate
for (ss = 0;; ss = xmalloc(len+1)) {
for (pp = pl; pp != end; pp = pp->next) {
if (pp->type == 'F') continue; // TODO fix this
for (i = len = 0; i<=pp->arg->c; i++)
len += snprintf(ss+len, ss ? INT_MAX : 0, " %s"+!i,
pp->arg->v[i] ? : ";"+(pp->next==end));
}
if (ss) return ss;
}
// TODO test output with case and function
// TODO add HERE documents back in
// TODO handle functions
}
// restore displaced filehandles, closing high filehandles they were copied to
static void unredirect(int *urd)
{
int *rr = urd+1, i;
if (!urd) return;
for (i = 0; i<*urd; i++, rr += 2) if (rr[0] != -1) {
// No idea what to do about fd exhaustion here, so Steinbach's Guideline.
dup2(rr[0], rr[1]);
close(rr[0]);
}
free(urd);
}
static struct sh_blockstack *clear_block(struct sh_blockstack *blk)
{
memset(blk, 0, sizeof(*blk));
blk->start = TT.ff->pl;
blk->run = 1;
blk->pout = -1;
return blk;
}
// when ending a block, free, cleanup redirects and pop stack.
static struct sh_pipeline *pop_block(void)
{
struct sh_pipeline *pl = 0;
struct sh_blockstack *blk = TT.ff->blk;
// when ending a block, free, cleanup redirects and pop stack.
if (blk->pout != -1) close(blk->pout);
unredirect(blk->urd);
llist_traverse(blk->fdelete, llist_free_arg);
free(blk->farg.v);
if (TT.ff->blk->next) {
pl = blk->start->end;
free(llist_pop(&TT.ff->blk));
} else clear_block(blk);
return pl;
}
// Push a new empty block to the stack
static void add_block(void)
{
struct sh_blockstack *blk = clear_block(xmalloc(sizeof(*blk)));
blk->next = TT.ff->blk;
TT.ff->blk = blk;
}
// Add entry to runtime function call stack
static void call_function(void)
{
// dlist in reverse order: TT.ff = current function, TT.ff->prev = globals
dlist_add_nomalloc((void *)&TT.ff, xzalloc(sizeof(struct sh_fcall)));
TT.ff = TT.ff->prev;
add_block();
// TODO caller needs to set pl, vars, func
// default $* is to copy previous
TT.ff->arg.v = TT.ff->next->arg.v;
TT.ff->arg.c = TT.ff->next->arg.c;
TT.ff->ifs = TT.ff->next->ifs;
}
// functions contain pipelines contain functions: prototype because loop
static void free_pipeline(void *pipeline);
static void free_function(struct sh_function *funky)
{
if (--funky->refcount) return;
free(funky->name);
llist_traverse(funky->pipeline, free_pipeline);
free(funky);
}
// TODO: old function-vs-source definition is "has variables", but no ff->func?
// returns 0 if source popped, nonzero if function popped
static int end_function(int funconly)
{
struct sh_fcall *ff = TT.ff;
int func = ff->next!=ff && ff->vars;
if (!func && funconly) return 0;
llist_traverse(ff->delete, llist_free_arg);
ff->delete = 0;
while (TT.ff->blk->next) pop_block();
pop_block();
// for a function, free variables and pop context
if (!func) return 0;
while (ff->varslen)
if (!(ff->vars[--ff->varslen].flags&VAR_NOFREE))
free(ff->vars[ff->varslen].str);
free(ff->vars);
free(TT.ff->blk);
if (ff->func) free_function(ff->func);
free(dlist_pop(&TT.ff));
return 1;
}
// TODO check every caller of run_subshell for error, or syntax_error() here
// from pipe() failure
// TODO need CLOFORK? CLOEXEC doesn't help if we don't exec...
// Pass environment and command string to child shell, return PID of child
static int run_subshell(char *str, int len)
{
pid_t pid;
//dprintf(2, "%d run_subshell %.*s\n", getpid(), len, str); debug_show_fds();
// The with-mmu path is significantly faster.
if (CFG_TOYBOX_FORK) {
if ((pid = fork())<0) perror_msg("fork");
else if (!pid) {
call_function();
if (str) {
do_source(0, fmemopen(str, len, "r"));
_exit(toys.exitval);
}
}
// On nommu vfork, exec /proc/self/exe, and pipe state data to ourselves.
} else {
int pipes[2];
unsigned i;
char **oldenv = environ, *ss = str ? : pl2str(TT.ff->pl->next, 0);
struct sh_vars **vv;
// open pipe to child
if (pipe(pipes) || 254 != dup2(pipes[0], 254)) return 1;
close(pipes[0]);
fcntl(pipes[1], F_SETFD, FD_CLOEXEC);
// vfork child with clean environment
environ = xzalloc(4*sizeof(char *));
*environ = getvar("PATH") ? : "PATH=";
pid = xpopen_setup(0, 0, subshell_callback);
// TODO what if pid -1? Handle process exhaustion.
// free entries added to end of environment by callback (shared heap)
free(environ[1]);
free(environ[2]);
free(environ);
environ = oldenv;
// marshall context to child
close(254);
dprintf(pipes[1], "%lld %u %u %u %u\n", TT.SECONDS,
TT.options, TT.LINENO, TT.pid, TT.bangpid);
for (i = 0, vv = visible_vars(); vv[i]; i++)
dprintf(pipes[1], "%u %lu\n%.*s", (unsigned)strlen(vv[i]->str),
vv[i]->flags, (int)strlen(vv[i]->str), vv[i]->str);
free(vv);
// send command
dprintf(pipes[1], "0 0\n%.*s\n", len, ss);
if (!str) free(ss);
close(pipes[1]);
}
return pid;
}
// Call subshell with either stdin/stdout redirected, return other end of pipe
static int pipe_subshell(char *s, int len, int out)
{
int pipes[2], *uu = 0, in = !out;
// Grab subshell data
if (pipe(pipes)) {
perror_msg("%.*s", len, s);
return -1;
}
// Perform input or output redirect and launch process (ignoring errors)
save_redirect(&uu, pipes[in], in);
close(pipes[in]);
fcntl(pipes[!in], F_SETFD, FD_CLOEXEC);
run_subshell(s, len);
fcntl(pipes[!in], F_SETFD, 0);
unredirect(uu);
return pipes[out];
}
// utf8 strchr: return wide char matched at wc from chrs, or 0 if not matched
// if len, save length of next wc (whether or not it's in list)
static int utf8chr(char *wc, char *chrs, int *len)
{
unsigned wc1, wc2;
int ll;
if (len) *len = 1;
if (!*wc) return 0;
if (0<(ll = utf8towc(&wc1, wc, 99))) {
if (len) *len = ll;
while (*chrs) {
if(1>(ll = utf8towc(&wc2, chrs, 99))) chrs++;
else {
if (wc1 == wc2) return wc1;
chrs += ll;
}
}
}
return 0;
}
// grab variable or special param (ala $$) up to len bytes. Return value.
// set *used to length consumed. Does not handle $* and $@
char *getvar_special(char *str, int len, int *used, struct arg_list **delete)
{
char *s = 0, *ss, cc = *str;
unsigned uu;
*used = 1;
if (cc == '-') {
s = ss = xmalloc(8);
if (TT.options&FLAG_i) *ss++ = 'i';
if (TT.options&OPT_B) *ss++ = 'B';
if (TT.options&FLAG_s) *ss++ = 's';
if (TT.options&FLAG_c) *ss++ = 'c';
*ss = 0;
} else if (cc == '?') s = xmprintf("%d", toys.exitval);
else if (cc == '$') s = xmprintf("%d", TT.pid);
else if (cc == '#') s = xmprintf("%d", TT.ff->arg.c ? TT.ff->arg.c-1 : 0);
else if (cc == '!') s = xmprintf("%d"+2*!TT.bangpid, TT.bangpid);
else {
delete = 0;
for (*used = uu = 0; *used<len && isdigit(str[*used]); ++*used)
uu = (10*uu)+str[*used]-'0';
if (*used) {
if (uu) uu += TT.ff->shift;
if (uu<TT.ff->arg.c) s = TT.ff->arg.v[uu];
} else if ((*used = varend(str)-str)) return getvar(str);
}
if (s) push_arg(delete, s);
return s;
}
#define WILD_SHORT 1 // else longest match
#define WILD_CASE 2 // case insensitive
#define WILD_ANY 4 // advance through pattern instead of str
// Returns length of str matched by pattern, or -1 if not all pattern consumed
static int wildcard_matchlen(char *str, int len, char *pattern, int plen,
struct sh_arg *deck, int flags)
{
struct sh_arg ant = {0}; // stack: of str offsets
long ss, pp, dd, best = -1;
int i, j, c, not;
// Loop through wildcards in pattern.
for (ss = pp = dd = 0; ;) {
if ((flags&WILD_ANY) && best!=-1) break;
// did we consume pattern?
if (pp==plen) {
if (ss>best) best = ss;
if (ss==len || (flags&WILD_SHORT)) break;
// attempt literal match?
} else if (dd>=deck->c || pp!=(long)deck->v[dd]) {
if (ss<len) {
if (flags&WILD_CASE) {
ss += getutf8(str+ss, len-ss, &c);
c = towupper(c);
pp += getutf8(pattern+pp, pp-plen, &i);
i = towupper(i);
} else c = str[ss++], i = pattern[pp++];
if (c==i) continue;
}
// Wildcard chars: |+@!*?()[]
} else {
c = pattern[pp++];
dd++;
if (c=='?' || ((flags&WILD_ANY) && c=='*')) {
ss += (i = getutf8(str+ss, len-ss, 0));
if (i) continue;
} else if (c=='*') {
// start with zero length match, don't record consecutive **
if (dd==1 || pp-2!=(long)deck->v[dd-1] || pattern[pp-2]!='*') {
arg_add(&ant, (void *)ss);
arg_add(&ant, 0);
}
continue;
} else if (c == '[') {
pp += (not = !!strchr("!^", pattern[pp]));
ss += getutf8(str+ss, len-ss, &c);
for (i = 0; pp<(long)deck->v[dd]; i = 0) {
pp += getutf8(pattern+pp, plen-pp, &i);
if (pattern[pp]=='-') {
++pp;
pp += getutf8(pattern+pp, plen-pp, &j);
if (not^(i<=c && j>=c)) break;
} else if (not^(i==c)) break;
}
if (i) {
pp = 1+(long)deck->v[dd++];
continue;
}
// ( preceded by +@!*?
} else { // TODO ( ) |
dd++;
continue;
}
}
// match failure
if (flags&WILD_ANY) {
ss = 0;
if (plen==pp) break;
continue;
}
// pop retry stack or return failure (TODO: seek to next | in paren)
while (ant.c) {
if ((c = pattern[(long)deck->v[--dd]])=='*') {
if (len<(ss = (long)ant.v[ant.c-2]+(long)++ant.v[ant.c-1])) ant.c -= 2;
else {
pp = (long)deck->v[dd++]+1;
break;
}
} else if (c == '(') dprintf(2, "TODO: (");
}
if (!ant.c) break;
}
free (ant.v);
return best;
}
static int wildcard_match(char *s, char *p, struct sh_arg *deck, int flags)
{
return wildcard_matchlen(s, strlen(s), p, strlen(p), deck, flags);
}
// TODO: test that * matches ""
// skip to next slash in wildcard path, passing count active ranges.
// start at pattern[off] and deck[*idx], return pattern pos and update *idx
char *wildcard_path(char *pattern, int off, struct sh_arg *deck, int *idx,
int count)
{
char *p, *old;
int i = 0, j = 0;
// Skip [] and nested () ranges within deck until / or NUL
for (p = old = pattern+off;; p++) {
if (!*p) return p;
while (*p=='/') {
old = p++;
if (j && !count) return old;
j = 0;
}
// Got wildcard? Return if start of name if out of count, else skip [] ()
if (*idx<deck->c && p-pattern == (long)deck->v[*idx]) {
if (!j++ && !count--) return old;
++*idx;
if (*p=='[') p = pattern+(long)deck->v[(*idx)++];
else if (*p=='(') while (*++p) if (p-pattern == (long)deck->v[*idx]) {
++*idx;
if (*p == ')') {
if (!i) break;
i--;
} else if (*p == '(') i++;
}
}
}
}
// TODO ** means this directory as well as ones below it, shopt -s globstar
// Filesystem traversal callback
// pass on: filename, portion of deck, portion of pattern,
// input: pattern+offset, deck+offset. Need to update offsets.
int do_wildcard_files(struct dirtree *node)
{
struct dirtree *nn;
char *pattern, *patend;
int lvl, ll = 0, ii = 0, rc;
struct sh_arg ant;
// Top level entry has no pattern in it
if (!node->parent) return DIRTREE_RECURSE;
// Find active pattern range
for (nn = node->parent; nn; nn = nn->parent) if (nn->parent) ii++;
pattern = wildcard_path(TT.wcpat, 0, TT.wcdeck, &ll, ii);
while (*pattern=='/') pattern++;
lvl = ll;
patend = wildcard_path(TT.wcpat, pattern-TT.wcpat, TT.wcdeck, &ll, 1);
// Don't include . entries unless explicitly asked for them
if (*node->name=='.' && *pattern!='.') return 0;
// Don't descend into non-directory (was called with DIRTREE_SYMFOLLOW)
if (*patend && !S_ISDIR(node->st.st_mode) && *node->name) return 0;
// match this filename from pattern to p in deck from lvl to ll
ant.c = ll-lvl;
ant.v = TT.wcdeck->v+lvl;
for (ii = 0; ii<ant.c; ii++) TT.wcdeck->v[lvl+ii] -= pattern-TT.wcpat;
rc = wildcard_matchlen(node->name, strlen(node->name), pattern,
patend-pattern, &ant, 0);
for (ii = 0; ii<ant.c; ii++) TT.wcdeck->v[lvl+ii] += pattern-TT.wcpat;
// Return failure or save exact match.
if (rc<0 || node->name[rc]) return 0;
if (!*patend) return DIRTREE_SAVE;
// Are there more wildcards to test children against?
if (TT.wcdeck->c!=ll) return DIRTREE_RECURSE;
// No more wildcards: check for child and return failure if it isn't there.
pattern = xmprintf("%s%s", node->name, patend);
rc = faccessat(dirtree_parentfd(node), pattern, F_OK, AT_SYMLINK_NOFOLLOW);
free(pattern);
if (rc) return 0;
// Save child and self. (Child could be trailing / but only one saved.)
while (*patend=='/' && patend[1]) patend++;
node->child = xzalloc(sizeof(struct dirtree)+1+strlen(patend));
node->child->parent = node;
strcpy(node->child->name, patend);
return DIRTREE_SAVE;
}
// Record active wildcard chars in output string
// *new start of string, oo offset into string, deck is found wildcards,
static void collect_wildcards(char *new, long oo, struct sh_arg *deck)
{
long bracket, *vv;
char cc = new[oo];
// Record unescaped/unquoted wildcard metadata for later processing
if (!deck->c) arg_add(deck, 0);
vv = (long *)deck->v;
// vv[0] used for paren level (bottom 16 bits) + bracket start offset<<16
// at end loop backwards through live wildcards to remove pending unmatched (
if (!cc) {
long ii = 0, jj = 65535&*vv, kk;
for (kk = deck->c; jj;) {
if (')' == (cc = new[vv[--kk]])) ii++;
else if ('(' == cc) {
if (ii) ii--;
else {
memmove(vv+kk, vv+kk+1, sizeof(long)*(deck->c-- -kk));
jj--;
}
}
}
if (deck->c) memmove(vv, vv+1, sizeof(long)*deck->c--);
return;
}
// Start +( range, or remove first char that isn't wildcard without (
if (deck->c>1 && vv[deck->c-1] == oo-1 && strchr("+@!*?", new[oo-1])) {
if (cc == '(') {
vv[deck->c-1] = oo;
return;
} else if (!strchr("*?", new[oo-1])) deck->c--;
}
// fall through to add wildcard, popping parentheses stack as necessary
if (strchr("|+@!*?", cc));
else if (cc == ')' && (65535&*vv)) --*vv;
// complete [range], discard wildcards within, add [, fall through to add ]
else if (cc == ']' && (bracket = *vv>>16)) {
// don't end range yet for [] or [^]
if (bracket+1 == oo || (bracket+2 == oo && strchr("!^", new[oo-1]))) return;
while (deck->c>1 && vv[deck->c-1]>=bracket) deck->c--;
*vv &= 65535;
arg_add(deck, (void *)bracket);
// Not a wildcard
} else {
// [ is speculative, don't add to deck yet, just record we saw it
if (cc == '[' && !(*vv>>16)) *vv = (oo<<16)+(65535&*vv);
return;
}
// add active wildcard location
arg_add(deck, (void *)oo);
}
// wildcard expand data against filesystem, and add results to arg list
// Note: this wildcard deck has extra argument at start (leftover from parsing)
static void wildcard_add_files(struct sh_arg *arg, char *pattern,
struct sh_arg *deck, struct arg_list **delete)
{
struct dirtree *dt;
char *pp;
int ll = 0;
// fast path: when no wildcards, add pattern verbatim
collect_wildcards("", 0, deck);
if (!deck->c) return arg_add(arg, pattern);
// Traverse starting with leading patternless path.
pp = wildcard_path(TT.wcpat = pattern, 0, TT.wcdeck = deck, &ll, 0);
pp = (pp==pattern) ? 0 : xstrndup(pattern, pp-pattern);
dt = dirtree_flagread(pp, DIRTREE_STATLESS|DIRTREE_SYMFOLLOW,
do_wildcard_files);
free(pp);
deck->c = 0;
// If no match save pattern, else free tree saving each path found.
if (!dt) return arg_add(arg, pattern);
while (dt) {
while (dt->child) dt = dt->child;
arg_add(arg, push_arg(delete, dirtree_path(dt, 0)));
do {
pp = (void *)dt;
if ((dt = dt->parent)) dt->child = dt->child->next;
free(pp);
} while (dt && !dt->child);
}
// TODO: test .*/../
}
// Copy string until } including escaped }
// if deck collect wildcards, and store terminator at deck->v[deck->c]
char *slashcopy(char *s, char *c, struct sh_arg *deck)
{
char *ss;
long ii, jj;
for (ii = 0; !strchr(c, s[ii]); ii++) if (s[ii] == '\\') ii++;
ss = xmalloc(ii+1);
for (ii = jj = 0; !strchr(c, s[jj]); ii++)
if ('\\'==(ss[ii] = s[jj++])) ss[ii] = s[jj++];
else if (deck) collect_wildcards(ss, ii, deck);
ss[ii] = 0;
if (deck) {
arg_add(deck, 0);
deck->v[--deck->c] = (void *)jj;
collect_wildcards("", 0, deck);
}
return ss;
}
#define NO_QUOTE (1<<0) // quote removal
#define NO_PATH (1<<1) // path expansion (wildcards)
#define NO_SPLIT (1<<2) // word splitting
#define NO_BRACE (1<<3) // {brace,expansion}
#define NO_TILDE (1<<4) // ~username/path
#define NO_NULL (1<<5) // Expand to "" instead of NULL
#define SEMI_IFS (1<<6) // Use ' ' instead of IFS to combine $*
// expand str appending to arg using above flag defines, add mallocs to delete
// if ant not null, save wildcard deck there instead of expanding vs filesystem
// returns 0 for success, 1 for error
static int expand_arg_nobrace(struct sh_arg *arg, char *str, unsigned flags,
struct arg_list **delete, struct sh_arg *ant)
{
char cc, qq = flags&NO_QUOTE, sep[6], *new = str, *s, *ss = ss, *ifs, *slice;
int ii = 0, oo = 0, xx, yy, dd, jj, kk, ll, mm;
struct sh_arg deck = {0};
// Tilde expansion
if (!(flags&NO_TILDE) && *str == '~') {
struct passwd *pw = 0;
ss = 0;
while (str[ii] && str[ii]!=':' && str[ii]!='/') ii++;
if (ii==1) {
if (!(ss = getvar("HOME")) || !*ss) pw = bufgetpwuid(getuid());
} else {
// TODO bufgetpwnam
pw = getpwnam(s = xstrndup(str+1, ii-1));
free(s);
}
if (pw) {
ss = pw->pw_dir;
if (!ss || !*ss) ss = "/";
}
if (ss) {
oo = strlen(ss);
s = xmprintf("%s%s", ss, str+ii);
if (str != new) free(new);
new = s;
}
}
// parameter/variable expansion and dequoting
if (!ant) ant = &deck;
for (; (cc = str[ii++]); str!=new && (new[oo] = 0)) {
struct sh_arg aa = {0};
int nosplit = 0;
// skip literal chars
if (!strchr("'\"\\$`"+2*(flags&NO_QUOTE), cc)) {
if (str != new) new[oo] = cc;
if (!(flags&NO_PATH) && !(qq&1)) collect_wildcards(new, oo, ant);
oo++;
continue;
}
// allocate snapshot if we just started modifying
if (str == new) {
new = xstrdup(new);
new[oo] = 0;
}
ifs = slice = 0;
// handle escapes and quoting
if (cc == '\\') {
if (!(qq&1) || (str[ii] && strchr("\"\\$`", str[ii])))
new[oo++] = str[ii] ? str[ii++] : cc;
} else if (cc == '"') qq++;
else if (cc == '\'') {
if (qq&1) new[oo++] = cc;
else {
qq += 2;
while ((cc = str[ii++]) != '\'') new[oo++] = cc;
}
// both types of subshell work the same, so do $( here not in '$' below
// TODO $((echo hello) | cat) ala $(( becomes $( ( retroactively
} else if (cc == '`' || (cc == '$' && str[ii] && strchr("([", str[ii]))) {
off_t pp = 0;
s = str+ii-1;
kk = parse_word(s, 1, 0)-s;
if (str[ii] == '[' || *toybuf == 255) {
struct sh_arg aa = {0};
long long ll;
// Expand $VARS in math string
ss = str+ii+1+(str[ii]=='(');
push_arg(delete, ss = xstrndup(ss, kk - (3+2*(str[ii]!='['))));
expand_arg_nobrace(&aa, ss, NO_PATH|NO_SPLIT, delete, 0);
s = ss = (aa.v && *aa.v) ? *aa.v : "";
free(aa.v);
// Recursively calculate result
if (!recalculate(&ll, &s, 0) || *s) {
error_msg("bad math: %s @ %ld", ss, (s-ss)+1);
goto fail;
}
ii += kk-1;
push_arg(delete, ifs = xmprintf("%lld", ll));
} else {
// Run subshell and trim trailing newlines
s += (jj = 1+(cc == '$'));
ii += --kk;
kk -= jj;
// Special case echo $(<input)
for (ss = s; isspace(*ss); ss++);
if (*ss != '<') ss = 0;
else {
while (isspace(*++ss));
if (!(ll = parse_word(ss, 0, 0)-ss)) ss = 0;
else {
jj = ll+(ss-s);
while (isspace(s[jj])) jj++;
if (jj != kk) ss = 0;
else {
jj = xcreate_stdio(ss = xstrndup(ss, ll), O_RDONLY|WARN_ONLY, 0);
free(ss);
}
}
}
// TODO what does \ in `` mean? What is echo `printf %s \$x` supposed to do?
// This has to be async so pipe buffer doesn't fill up
if (!ss) jj = pipe_subshell(s, kk, 0);
if ((ifs = readfd(jj, 0, &pp)))
for (kk = strlen(ifs); kk && ifs[kk-1]=='\n'; ifs[--kk] = 0);
close(jj);
}
// $VARIABLE expansions
} else if (cc == '$') {
cc = *(ss = str+ii++);
if (cc=='\'') {
for (s = str+ii; *s != '\''; oo += wcrtomb(new+oo, unescape2(&s, 0),0));
ii = s-str+1;
continue;
} else if (cc=='"' && !(qq&1)) {
qq++;
continue;
} else if (cc == '{') {
// Skip escapes to find }, parse_word() guarantees ${} terminates
for (cc = *++ss; str[ii] != '}'; ii++) if (str[ii]=='\\') ii++;
ii++;
if (cc == '}') ifs = (void *)1;
else if (strchr("#!", cc)) ss++;
if (!(jj = varend(ss)-ss)) while (isdigit(ss[jj])) jj++;
if (!jj && strchr("#$_*", *ss)) jj++;
// parameter or operator? Maybe not a prefix: ${#-} vs ${#-x}
if (!jj && strchr("-?@", *ss)) if (ss[++jj]!='}' && ss[-1]!='{') ss--;
slice = ss+jj; // start of :operation
if (!jj) {
// literal ${#} or ${!} wasn't a prefix
if (strchr("#!", cc)) ifs = getvar_special(--ss, 1, &kk, delete);
else ifs = (void *)1; // unrecognized char ala ${~}
} else if (ss[-1]=='{'); // not prefix, fall through
else if (cc == '#') { // TODO ${#x[@]}
dd = !!strchr("@*", *ss); // For ${#@} or ${#*} do normal ${#}
ifs = getvar_special(ss-dd, jj, &kk, delete) ? : "";
if (!dd) push_arg(delete, ifs = xmprintf("%zu", strlen(ifs)));
// ${!@} ${!@Q} ${!x} ${!x@} ${!x@Q} ${!x#} ${!x[} ${!x[*]}
} else if (cc == '!') { // TODO: ${var[@]} array
// special case: normal varname followed by @} or *} = prefix list
if (ss[jj] == '*' || (ss[jj] == '@' && !isalpha(ss[jj+1]))) {
struct sh_vars **vv = visible_vars();
for (slice++, kk = 0; vv[kk]; kk++) {
if (vv[kk]->flags&VAR_WHITEOUT) continue;
if (!strncmp(s = vv[kk]->str, ss, jj))
arg_add(&aa, push_arg(delete, s = xstrndup(s, stridx(s, '='))));
}
if (aa.c) push_arg(delete, aa.v);
free(vv);
// else dereference to get new varname, discarding if none, check err
} else {
// First expansion
if (strchr("@*", *ss)) { // special case ${!*}/${!@}
expand_arg_nobrace(&aa, "\"$*\"", NO_PATH|NO_SPLIT, delete, 0);
ifs = *aa.v;
free(aa.v);
memset(&aa, 0, sizeof(aa));
jj = 1;
} else ifs = getvar_special(ss, jj, &jj, delete);
slice = ss+jj;
// Second expansion
if (!jj) ifs = (void *)1;
else if (ifs && *(ss = ifs)) {
if (strchr("@*", cc)) {
aa.c = TT.ff->arg.c-1;
aa.v = TT.ff->arg.v+1;
jj = 1;
} else ifs = getvar_special(ifs, strlen(ifs), &jj, delete);
if (ss && ss[jj]) {
ifs = (void *)1;
slice = ss+strlen(ss);
}
}
}
}
// Substitution error?
if (ifs == (void *)1) {
barf:
if (!(((unsigned long)ifs)>>1)) ifs = "bad substitution";
error_msg("%.*s: %s", (int)(slice-ss), ss, ifs);
goto fail;
}
} else jj = 1;
// Resolve unprefixed variables
if (strchr("{$", ss[-1])) {
if (strchr("@*", cc)) {
aa.c = TT.ff->arg.c-1;
aa.v = TT.ff->arg.v+1;
} else {
ifs = getvar_special(ss, jj, &jj, delete);
if (!jj) {
if (ss[-1] == '{') goto barf;
new[oo++] = '$';
ii--;
continue;
} else if (ss[-1] != '{') ii += jj-1;
}
}
}
// combine before/ifs/after sections & split words on $IFS in ifs
// keep oo bytes of str before (already parsed)
// insert ifs (active for wildcards+splitting)
// keep str+ii after (still to parse)
// Fetch separator to glue string back together with
*sep = 0;
if (((qq&1) && cc=='*') || (flags&NO_SPLIT)) {
unsigned wc;
nosplit++;
if (flags&SEMI_IFS) strcpy(sep, " ");
// TODO what if separator is bigger? Need to grab 1 column of combining chars
else if (0<(dd = utf8towc(&wc, TT.ff->ifs, 4)))
sprintf(sep, "%.*s", dd, TT.ff->ifs);
}
// when aa proceed through entries until NULL, else process ifs once
mm = yy = 0;
do {
// get next argument
if (aa.c) ifs = aa.v[mm++] ? : "";
// Are we performing surgery on this argument?
if (slice && *slice != '}') {
dd = slice[xx = (*slice == ':')];
if (!ifs || (xx && !*ifs)) {
if (strchr("-?=", dd)) { // - use default = assign default ? error
push_arg(delete, ifs = slashcopy(slice+xx+1, "}", 0));
if (dd == '?' || (dd == '=' &&
!(setvar(s = xmprintf("%.*s=%s", (int)(slice-ss), ss, ifs)))))
goto barf; // TODO ? exits past "source" boundary
}
} else if (dd == '-'); // NOP when ifs not empty
// use alternate value
else if (dd == '+')
push_arg(delete, ifs = slashcopy(slice+xx+1, "}", 0));
else if (xx) { // ${x::}
long long la = 0, lb = LLONG_MAX, lc = 1;
ss = ++slice;
if ((lc = recalculate(&la, &ss, 0)) && *ss == ':') {
ss++;
lc = recalculate(&lb, &ss, 0);
}
if (!lc || *ss != '}') {
for (s = ss; *s != '}' && *s != ':'; s++);
error_msg("bad %.*s @ %ld", (int)(s-slice), slice, ss-slice);
//TODO fix error message
goto fail;
}
// This isn't quite what bash does, but close enough.
if (!(lc = aa.c)) lc = strlen(ifs);
else if (!la && !yy && strchr("@*", *slice)) {
aa.v--; // ${*:0} shows $0 even though default is 1-indexed
aa.c++;
yy++;
}
if (la<0 && (la += lc)<0) continue;
if (lb<0) lb = lc+lb-la;
if (aa.c) {
if (mm<la || mm>=la+lb) continue;
} else if (la>=lc || lb<0) ifs = "";
else if (la+lb>=lc) ifs += la;
else if (!*delete || ifs != (*delete)->arg)
push_arg(delete, ifs = xmprintf("%.*s", (int)lb, ifs+la));
else {
for (dd = 0; dd<lb ; dd++) if (!(ifs[dd] = ifs[dd+la])) break;
ifs[dd] = 0;
}
} else if (strchr("#%^,", *slice)) {
struct sh_arg wild = {0};
char buf[8];
s = slashcopy(slice+(xx = slice[1]==*slice)+1, "}", &wild);
// ${x^pat} ${x^^pat} uppercase ${x,} ${x,,} lowercase (no pat = ?)
if (strchr("^,", *slice)) {
for (ss = ifs; *ss; ss += dd) {
dd = getutf8(ss, 4, &jj);
if (!*s || 0<wildcard_match(ss, s, &wild, WILD_ANY)) {
ll = ((*slice=='^') ? towupper : towlower)(jj);
// Of COURSE unicode case switch can change utf8 encoding length
// Lower case U+0069 becomes u+0130 in turkish.
// Greek U+0390 becomes 3 characters TODO test this
if (ll != jj) {
yy = ss-ifs;
if (!*delete || (*delete)->arg!=ifs)
push_arg(delete, ifs = xstrdup(ifs));
if (dd != (ll = wctoutf8(buf, ll))) {
if (dd<ll)
ifs = (*delete)->arg = xrealloc(ifs, strlen(ifs)+1+dd-ll);
memmove(ifs+yy+dd-ll, ifs+yy+ll, strlen(ifs+yy+ll)+1);
}
memcpy(ss = ifs+yy, buf, dd = ll);
}
}
if (!xx) break;
}
// ${x#y} remove shortest prefix ${x##y} remove longest prefix
} else if (*slice=='#') {
if (0<(dd = wildcard_match(ifs, s, &wild, WILD_SHORT*!xx)))
ifs += dd;
// ${x%y} ${x%%y} suffix
} else if (*slice=='%') {
for (ss = ifs+strlen(ifs), yy = -1; ss>=ifs; ss--) {
if (0<(dd = wildcard_match(ss, s, &wild, WILD_SHORT*xx))&&!ss[dd])
{
yy = ss-ifs;
if (!xx) break;
}
}
if (yy != -1) {
if (*delete && (*delete)->arg==ifs) ifs[yy] = 0;
else push_arg(delete, ifs = xstrndup(ifs, yy));
}
}
free(s);
free(wild.v);
// ${x/pat/sub} substitute ${x//pat/sub} global ${x/#pat/sub} begin
// ${x/%pat/sub} end ${x/pat} delete pat (x can be @ or *)
} else if (*slice=='/') {
struct sh_arg wild = {0};
s = slashcopy(ss = slice+(xx = !!strchr("/#%", slice[1]))+1, "/}",
&wild);
ss += (long)wild.v[wild.c];
ss = (*ss == '/') ? slashcopy(ss+1, "}", 0) : 0;
jj = ss ? strlen(ss) : 0;
ll = 0;
for (ll = 0; ifs[ll];) {
// TODO nocasematch option
if (0<(dd = wildcard_match(ifs+ll, s, &wild, 0))) {
char *bird = 0;
if (slice[1]=='%' && ifs[ll+dd]) {
ll++;
continue;
}
if (*delete && (*delete)->arg==ifs) {
if (jj==dd) memcpy(ifs+ll, ss, jj);
else if (jj<dd) sprintf(ifs+ll, "%s%s", ss, ifs+ll+dd);
else bird = ifs;
} else bird = (void *)1;
if (bird) {
ifs = xmprintf("%.*s%s%s", ll, ifs, ss ? : "", ifs+ll+dd);
if (bird != (void *)1) {
free(bird);
(*delete)->arg = ifs;
} else push_arg(delete, ifs);
}
if (slice[1]!='/') break;
} else ll++;
if (slice[1]=='#') break;
}
// ${x@QEPAa} Q=$'blah' E=blah without the $'' wrap, P=expand as $PS1
// A=declare that recreates var a=attribute flags
// x can be @*
// } else if (*slice=='@') {
// TODO test x can be @ or *
} else {
// TODO test ${-abc} as error
ifs = slice;
goto barf;
}
// TODO: $((a=42)) can change var, affect lifetime
// must replace ifs AND any previous output arg[] within pointer strlen()
// also x=;echo $x${x:=4}$x
}
// Nothing left to do?
if (!ifs) break;
if (!*ifs && !qq) continue;
// loop within current ifs checking region to split words
do {
// find end of (split) word
if ((qq&1) || nosplit) ss = ifs+strlen(ifs);
else for (ss = ifs; *ss; ss += kk)
if (utf8chr(ss, TT.ff->ifs, &kk)) break;
// when no prefix, not splitting, no suffix: use existing memory
if (!oo && !*ss && !((mm==aa.c) ? str[ii] : nosplit)) {
if (qq || ss!=ifs) {
if (!(flags&NO_PATH))
for (jj = 0; ifs[jj]; jj++) collect_wildcards(ifs, jj, ant);
wildcard_add_files(arg, ifs, &deck, delete);
}
continue;
}
// resize allocation and copy next chunk of IFS-free data
jj = (mm == aa.c) && !*ss;
new = xrealloc(new, oo + (ss-ifs) + ((nosplit&!jj) ? strlen(sep) : 0) +
(jj ? strlen(str+ii) : 0) + 1);
dd = sprintf(new + oo, "%.*s%s", (int)(ss-ifs), ifs,
(nosplit&!jj) ? sep : "");
if (flags&NO_PATH) oo += dd;
else while (dd--) collect_wildcards(new, oo++, ant);
if (jj) break;
// If splitting, keep quoted, non-blank, or non-whitespace separator
if (!nosplit) {
if (qq || *new || *ss) {
push_arg(delete, new = xrealloc(new, strlen(new)+1));
wildcard_add_files(arg, new, &deck, delete);
new = xstrdup(str+ii);
}
qq &= 1;
oo = 0;
}
// Skip trailing seperator (combining whitespace)
kk = 0;
while ((jj = utf8chr(ss, TT.ff->ifs, &ll))) {
if (!iswspace(jj) && kk++) break;
ss += ll;
}
} while (*(ifs = ss));
} while (!(mm == aa.c));
}
// TODO globbing * ? [] +() happens after variable resolution
// TODO test word splitting completely eliminating argument when no non-$IFS data left
// wordexp keeps pattern when no matches
// TODO test NO_SPLIT cares about IFS, see also trailing \n
// Record result.
if (*new || qq) {
if (str != new) push_arg(delete, new);
wildcard_add_files(arg, new, &deck, delete);
new = 0;
}
// return success after freeing
arg = 0;
fail:
if (str != new) free(new);
free(deck.v);
if (ant!=&deck && ant->v) collect_wildcards("", 0, ant);
return !!arg;
}
struct sh_brace {
struct sh_brace *next, *prev, *stack;
int active, cnt, idx, commas[];
};
static int brace_end(struct sh_brace *bb)
{
return bb->commas[(bb->cnt<0 ? 0 : bb->cnt)+1];
}
// expand braces (ala {a,b,c}) and call expand_arg_nobrace() each permutation
static int expand_arg(struct sh_arg *arg, char *old, unsigned flags,
struct arg_list **delete)
{
struct sh_brace *bb = 0, *blist = 0, *bstk, *bnext;
int i, j, k, x;
char *s, *ss;
// collect brace spans
if ((TT.options&OPT_B) && !(flags&NO_BRACE)) for (i = 0; ; i++) {
// skip quoted/escaped text
while ((s = parse_word(old+i, 1, 0)) != old+i) i += s-(old+i);
// stop at end of string if we haven't got any more open braces
if (!bb && !old[i]) break;
// end a brace?
if (bb && (!old[i] || old[i] == '}')) {
bb->active = bb->commas[bb->cnt+1] = i;
// pop brace from bb into bnext
for (bnext = bb; bb && bb->active; bb = (bb==blist) ? 0 : bb->prev);
// Is this a .. span?
j = 1+*bnext->commas;
if (old[i] && !bnext->cnt && i-j>=4) {
// a..z span? Single digit numbers handled here too. TODO: utf8
if (old[j+1]=='.' && old[j+2]=='.') {
bnext->commas[2] = old[j];
bnext->commas[3] = old[j+3];
k = 0;
if (old[j+4]=='}' ||
(sscanf(old+j+4, "..%u}%n", bnext->commas+4, &k) && k))
bnext->cnt = -1;
}
// 3..11 numeric span?
if (!bnext->cnt) {
for (k=0, j = 1+*bnext->commas; k<3; k++, j += x)
if (!sscanf(old+j, "..%u%n"+2*!k, bnext->commas+2+k, &x)) break;
if (old[j] == '}') bnext->cnt = -2;
}
// Increment goes in the right direction by at least 1
if (bnext->cnt) {
if (!bnext->commas[4]) bnext->commas[4] = 1;
if ((bnext->commas[3]-bnext->commas[2]>0) != (bnext->commas[4]>0))
bnext->commas[4] *= -1;
}
}
// discard unterminated span, or commaless span that wasn't x..y
if (!old[i] || !bnext->cnt)
free(dlist_pop((blist == bnext) ? &blist : &bnext));
// starting brace
} else if (old[i] == '{') {
dlist_add_nomalloc((void *)&blist,
(void *)(bb = xzalloc(sizeof(struct sh_brace)+34*4)));
bb->commas[0] = i;
// no active span?
} else if (!bb) continue;
// add a comma to current span
else if (bb && old[i] == ',') {
if (bb->cnt && !(bb->cnt&31)) {
dlist_lpop(&blist);
dlist_add_nomalloc((void *)&blist,
(void *)(bb = xrealloc(bb, sizeof(struct sh_brace)+(bb->cnt+34)*4)));
}
bb->commas[++bb->cnt] = i;
}
}
// TODO NO_SPLIT with braces? (Collate with spaces?)
// If none, pass on verbatim
if (!blist) return expand_arg_nobrace(arg, old, flags, delete, 0);
// enclose entire range in top level brace.
(bstk = xzalloc(sizeof(struct sh_brace)+8))->commas[1] = strlen(old)+1;
bstk->commas[0] = -1;
// loop through each combination
for (;;) {
// Brace expansion can't be longer than original string. Keep start to {
s = ss = xmalloc(bstk->commas[1]);
// Append output from active braces to string
for (bb = blist; bb; bb = (bnext == blist) ? 0 : bnext) {
// If this brace already tip of stack, pop it. (We'll re-add in a moment.)
if (bstk == bb) bstk = bstk->stack;
// if bb is within bstk, save prefix text from bstk's "," to bb's "{"
if (brace_end(bstk)>bb->commas[0]) {
i = bstk->commas[bstk->idx]+1;
s = stpncpy(s, old+i, bb->commas[0]-i);
}
else bstk = bstk->stack; // bb past bstk so done with old bstk, pop it
// push self onto stack as active
bb->stack = bstk;
bb->active = 1;
bstk = bnext = bb;
// Find next active range: skip inactive spans from earlier/later commas
while ((bnext = (bnext->next==blist) ? 0 : bnext->next)) {
// past end of this brace (always true for a..b ranges)
if ((i = bnext->commas[0])>brace_end(bb)) break;
// in this brace but not this section
if (i<bb->commas[bb->idx] || i>bb->commas[bb->idx+1]) {
bnext->active = 0;
bnext->stack = 0;
// in this section
} else break;
}
// is next span past this range?
if (!bnext || bb->cnt<0 || bnext->commas[0]>bb->commas[bb->idx+1]) {
// output uninterrupted span
if (bb->cnt<0) {
k = bb->commas[2]+bb->commas[4]*bb->idx;
s += sprintf(s, (bb->cnt==-1) ? "\\%c"+!ispunct(k) : "%d", k);
} else {
i = bb->commas[bstk->idx]+1;
s = stpncpy(s, old+i, bb->commas[bb->idx+1]-i);
}
// While not sibling, output tail and pop
while (!bnext || bnext->commas[0]>brace_end(bstk)) {
if (!(bb = bstk->stack)) break;
i = brace_end(bstk)+1; // start of span
j = bb->commas[bb->idx+1]; // enclosing comma span (can't be a..b)
while (bnext) {
if (bnext->commas[0]<j) {
j = bnext->commas[0];// sibling
break;
} else if (brace_end(bb)>bnext->commas[0])
bnext = (bnext->next == blist) ? 0 : bnext->next;
else break;
}
s = stpncpy(s, old+i, j-i);
// if next is sibling but parent _not_ a sibling, don't pop
if (bnext && bnext->commas[0]<brace_end(bb)) break;
bstk = bb;
}
}
}
// Save result, aborting on expand error
if (expand_arg_nobrace(arg, push_arg(delete, ss), flags, delete, 0)) {
llist_traverse(blist, free);
return 1;
}
// increment
for (bb = blist->prev; bb; bb = (bb == blist) ? 0 : bb->prev) {
if (!bb->stack) continue;
else if (bb->cnt<0) {
if (abs(bb->commas[2]-bb->commas[3]) < abs(++bb->idx*bb->commas[4]))
bb->idx = 0;
else break;
} else if (++bb->idx > bb->cnt) bb->idx = 0;
else break;
}
// if increment went off left edge, done expanding
if (!bb) break;
}
llist_traverse(blist, free);
return 0;
}
// Expand exactly one arg, returning NULL on error.
static char *expand_one_arg(char *new, unsigned flags, struct arg_list **del)
{
struct sh_arg arg = {0};
char *s = 0;
if (!expand_arg(&arg, new, flags|NO_PATH|NO_SPLIT, del))
if (!(s = *arg.v) && (flags&(SEMI_IFS|NO_NULL))) s = "";
free(arg.v);
return s;
}
// TODO |&
// Expand arguments and perform redirections. Return new process object with
// expanded args. This can be called from command or block context.
static struct sh_process *expand_redir(struct sh_arg *arg, int skip, int *urd)
{
struct sh_process *pp;
char *s = s, *ss, *sss, *cv = 0;
int j, to, from, here = 0;
TT.hfd = 10;
pp = xzalloc(sizeof(struct sh_process));
pp->urd = urd;
pp->raw = arg;
// When we redirect, we copy each displaced filehandle to restore it later.
// Expand arguments and perform redirections
for (j = skip; j<arg->c; j++) {
int saveclose = 0, bad = 0;
if (!strcmp(s = arg->v[j], "!")) {
pp->flags ^= PFLAG_NOT;
continue;
}
// Handle <() >() redirectionss
if ((*s == '<' || *s == '>') && s[1] == '(') {
int new = pipe_subshell(s+2, strlen(s+2)-1, *s == '>');
// Grab subshell data
if (new == -1) {
pp->exit = 1;
return pp;
}
save_redirect(&pp->urd, -2, new);
// bash uses /dev/fd/%d which requires /dev/fd to be a symlink to
// /proc/self/fd so we just produce that directly.
arg_add_del(&pp->arg, ss = xmprintf("/proc/self/fd/%d", new),&pp->delete);
continue;
}
// Is this a redirect? s = prefix, ss = operator
ss = s + redir_prefix(arg->v[j]);
sss = ss + anystart(ss, (void *)redirectors);
if (ss == sss) {
// Nope: save/expand argument and loop
if (expand_arg(&pp->arg, s, 0, &pp->delete)) {
pp->exit = 1;
return pp;
}
continue;
} else if (j+1 >= arg->c) {
// redirect needs one argument
s = "\\n";
break;
}
sss = arg->v[++j];
// It's a redirect: for [to]<from s = start of [to], ss = <, sss = from
if (isdigit(*s) && ss-s>5) break;
// expand arguments for everything but << and <<-
if (strncmp(ss, "<<", 2) && ss[2] != '<') {
struct sh_arg tmp = {0};
if (!expand_arg(&tmp, sss, 0, &pp->delete) && tmp.c == 1) sss = *tmp.v;
else {
if (tmp.c > 1) error_msg("%s: ambiguous redirect", sss);
s = 0;
}
free(tmp.v);
if (!s) break;
}
// Parse the [fd] part of [fd]<name
to = *ss != '<';
if (isdigit(*s)) to = atoi(s);
else if (*s == '{') {
if (*varend(s+1) != '}') break;
// when we close a filehandle, we _read_ from {var}, not write to it
if ((!strcmp(ss, "<&") || !strcmp(ss, ">&")) && !strcmp(sss, "-")) {
if (!(ss = getvar(s+1))) break;
to = atoi(ss); // TODO trailing garbage?
if (save_redirect(&pp->urd, -1, to)) break;
close(to);
continue;
// record high file descriptor in {to}<from environment variable
} else {
// we don't save this, it goes in the env var and user can close it.
if (-1 == (to = next_hfd())) break;
cv = xmprintf("%.*s=%d", (int)(ss-s-2), s+1, to);
}
}
// HERE documents?
if (!strcmp(ss, "<<<") || !strcmp(ss, "<<-") || !strcmp(ss, "<<")) {
char *tmp = getvar("TMPDIR");
int i, len, zap = (ss[2] == '-'), x = !ss[strcspn(ss, "\"'")];
// store contents in open-but-deleted /tmp file.
tmp = xmprintf("%s/sh-XXXXXX", tmp ? tmp : "/tmp");
if ((from = mkstemp(tmp))>=0) {
if (unlink(tmp)) bad++;
// write contents to file (if <<< else <<) then lseek back to start
else if (ss[2] == '<') {
if (!(ss = expand_one_arg(sss, 0, 0))) {
s = 0;
break;
}
len = strlen(ss);
if (len != writeall(from, ss, len)) bad++;
if (ss != sss) free(ss);
} else {
struct sh_arg *hh = arg+here++;
for (i = 0; i<hh->c; i++) {
ss = hh->v[i];
sss = 0;
// TODO audit this ala man page
// expand_parameter, commands, and arithmetic
if (x && !(ss = sss = expand_one_arg(ss, ~SEMI_IFS, 0))) {
s = 0;
break;
}
while (zap && *ss == '\t') ss++;
x = writeall(from, ss, len = strlen(ss));
free(sss);
if (len != x) break;
}
if (i != hh->c) bad++;
}
if (!bad && lseek(from, 0, SEEK_SET)) bad++;
if (bad) close(from);
} else bad++;
free(tmp);
if (bad) break;
// from is fd<<2 (new fd to dup2() after vfork()) plus
// 2 if we should close(from>>2) after dup2(from>>2, to),
// 1 if we should close but dup for nofork recovery (ala <&2-)
// Handle file descriptor duplication/close (&> &>> <& >& with number or -)
// These redirect existing fd so nothing to open()
} else if (*ss == '&' || ss[1] == '&') {
// is there an explicit fd?
for (ss = sss; isdigit(*ss); ss++);
if (ss-sss>5 || (*ss && (*ss != '-' || ss[1]))) {
if (*ss=='&') ss++;
saveclose = 4;
goto notfd;
}
from = (ss==sss) ? to : atoi(sss);
saveclose = 2-(*ss == '-');
} else {
notfd:
// Permissions to open external file with: < > >> <& >& <> >| &>> &>
if (!strcmp(ss, "<>")) from = O_CREAT|O_RDWR;
else if (strstr(ss, ">>")) from = O_CREAT|O_APPEND|O_WRONLY;
else {
from = (*ss == '<') ? O_RDONLY : O_CREAT|O_WRONLY|O_TRUNC;
if (!strcmp(ss, ">") && (TT.options&OPT_C)) {
struct stat st;
// Not _just_ O_EXCL: > /dev/null allowed
if (stat(sss, &st) || !S_ISREG(st.st_mode)) from |= O_EXCL;
}
}
// we expect /dev/fd/# and /dev/{stdin,stdout,stderr} to be in /dev
// TODO: /dev/{tcp,udp}/host/port
// Open the file
if (-1 == (from = xcreate_stdio(sss, from|WARN_ONLY, 0666))) {
s = 0;
break;
}
}
// perform redirect, saving displaced "to".
if (save_redirect(&pp->urd, from, to)) bad++;
// Do we save displaced "to" in env variable instead of undo list?
if (cv) {
--*pp->urd;
if (!setvar(cv)) bad++;
cv = 0;
}
if ((saveclose&1) && save_redirect(&pp->urd, -1, from)) bad++;
if ((saveclose&4) && save_redirect(&pp->urd, from, 2)) bad++;
if (!(saveclose&2)) close(from);
if (bad) break;
}
// didn't parse everything?
if (j != arg->c) {
if (s) syntax_err(s);
if (!pp->exit) pp->exit = 1;
free(cv);
}
return pp;
}
// Call binary, or run script via xexec("sh --")
static void sh_exec(char **argv)
{
char *pp = getvar("PATH" ? : _PATH_DEFPATH), *cc = TT.isexec ? : *argv, *ss,
**sss = 0, **oldenv = environ, **argv2;
struct string_list *sl;
if (getpid() != TT.pid) signal(SIGINT, SIG_DFL); // TODO: restore all?
errno = ENOENT;
if (strchr(ss = cc, '/')) {
if (access(ss, X_OK)) ss = 0;
} else for (sl = find_in_path(pp, cc); sl || (ss = 0); free(llist_pop(&sl)))
if (!access(ss = sl->str, X_OK)) break;
if (ss) {
struct sh_vars **vv = visible_vars();
struct sh_arg aa;
unsigned uu, argc;
// convert vars in-place and use original sh_arg alloc to add one more
aa.v = environ = (void *)vv;
for (aa.c = uu = 0; vv[uu]; uu++) {
if ((vv[uu]->flags&(VAR_WHITEOUT|VAR_EXPORT))==VAR_EXPORT) {
if (*(pp = vv[uu]->str)=='_' && pp[1]=='=') sss = aa.v+aa.c;
aa.v[aa.c++] = pp;
}
}
aa.v[aa.c] = 0;
if (!sss) {
arg_add(&aa, 0);
sss = aa.v+aa.c-1;
}
*sss = xmprintf("_=%s", ss);
// exec or source
execve(ss, argv, environ);
if (errno == ENOEXEC) {
for (argc = 0; argv[argc]; argc++);
argv2 = xmalloc((argc+3)*sizeof(char *));
memcpy(argv2+3, argv+1, argc*sizeof(char *));
argv2[0] = "sh";
argv2[1] = "--";
argv2[2] = ss;
xexec(argv2);
free(argv2);
}
environ = oldenv;
free(*sss);
free(aa.v);
}
perror_msg("%s", *argv);
if (!TT.isexec) _exit(127);
llist_traverse(sl, free);
}
// Execute a single command at TT.ff->pl
static struct sh_process *run_command(void)
{
char *s, *ss, *sss;
struct sh_arg *arg = TT.ff->pl->arg;
int envlen, funk = TT.funcslen, jj = 0, prefix = 0;
struct sh_process *pp;
// Count leading variable assignments
for (envlen = 0; envlen<arg->c; envlen++)
if ((ss = varend(arg->v[envlen]))==arg->v[envlen] || ss[*ss=='+']!='=')
break;
pp = expand_redir(arg, envlen, 0);
// Are we calling a shell function? TODO binary search
if (pp->arg.c && !strchr(*pp->arg.v, '/'))
for (funk = 0; funk<TT.funcslen; funk++)
if (!strcmp(*pp->arg.v, TT.functions[funk]->name)) break;
// Create new function context to hold local vars?
if (funk != TT.funcslen || (envlen && pp->arg.c) || TT.ff->blk->pipe) {
call_function();
// TODO function needs to run asynchronously in pipeline
if (funk != TT.funcslen) {
TT.ff->delete = pp->delete;
pp->delete = 0;
}
addvar(0, TT.ff); // function context (not source) so end_function deletes
prefix = 1; // create local variables for function prefix assignment
}
// perform any assignments
if (envlen) for (; jj<envlen && !pp->exit; jj++) {
struct sh_vars *vv;
if ((sss = expand_one_arg(ss = arg->v[jj], SEMI_IFS, 0))) {
if (!prefix && sss==ss) sss = xstrdup(sss);
if ((vv = setvar_long(sss, sss!=ss, prefix ? TT.ff : TT.ff->prev))) {
if (prefix) vv->flags |= VAR_EXPORT;
continue;
}
}
pp->exit = 1;
break;
}
// Do the thing
if (pp->exit || envlen==arg->c) s = 0; // leave $_ alone
else if (!pp->arg.c) s = ""; // nothing to do but blank $_
// TODO: call functions() FUNCTION
// TODO what about "echo | x=1 | export fruit", must subshell? Test this.
// Several NOFORK can just NOP in a pipeline? Except ${a?b} still errors
// call shell function
else if (funk != TT.funcslen) {
s = 0; // $_ set on return, not here
(TT.ff->func = TT.functions[funk])->refcount++;
TT.ff->pl = TT.ff->func->pipeline;
TT.ff->arg = pp->arg;
// TODO: unredirect(pp->urd) called below but haven't traversed function yet
} else {
struct toy_list *tl = toy_find(*pp->arg.v);
jj = tl ? tl->flags : 0;
TT.pp = pp;
s = pp->arg.v[pp->arg.c-1];
sss = pp->arg.v[pp->arg.c];
//dprintf(2, "%d run command %p %s\n", getpid(), TT.ff, *pp->arg.v); debug_show_fds();
// TODO handle ((math)): else if (!strcmp(*pp->arg.v, "(("))
// TODO: figure out when can exec instead of forking, ala sh -c blah
// Is this command a builtin that should run in this process?
if ((jj&TOYFLAG_NOFORK) || ((jj&TOYFLAG_MAYFORK) && !prefix)) {
sigjmp_buf rebound;
char temp[jj = offsetof(struct toy_context, rebound)];
// This fakes lots of what toybox_main() does.
memcpy(&temp, &toys, jj);
memset(&toys, 0, jj);
// The compiler complains "declaration does not declare anything" if we
// name the union in TT, only works WITHOUT name. So we can't
// sizeof(union) instead offsetof() first thing after union to get size.
memset(&TT, 0, offsetof(struct sh_data, SECONDS));
if (!sigsetjmp(rebound, 1)) {
toys.rebound = &rebound;
//dprintf(2, "%d builtin", getpid()); for (int xx = 0; xx<=pp->arg.c; xx++) dprintf(2, "{%s}", pp->arg.v[xx]); dprintf(2, "\n");
toy_singleinit(tl, pp->arg.v);
tl->toy_main();
xflush(0);
}
toys.rebound = 0;
pp->exit = toys.exitval;
if (toys.optargs != toys.argv+1) free(toys.optargs);
if (toys.old_umask) umask(toys.old_umask);
memcpy(&toys, &temp, jj);
} else if (-1==(pp->pid = xpopen_setup(pp->arg.v, 0, sh_exec)))
perror_msg("%s: vfork", *pp->arg.v);
}
// cleanup process
unredirect(pp->urd);
pp->urd = 0;
if (prefix && funk == TT.funcslen) end_function(0);
if (s) setvarval("_", s);
return pp;
}
static int free_process(struct sh_process *pp)
{
int rc;
if (!pp) return 127;
rc = pp->exit;
llist_traverse(pp->delete, llist_free_arg);
free(pp);
return rc;
}
// if then fi for while until select done done case esac break continue return
// Free one pipeline segment.
static void free_pipeline(void *pipeline)
{
struct sh_pipeline *pl = pipeline;
int i, j;
if (!pl) return;
// free either function or arguments and HERE doc contents
if (pl->type == 'F') {
free_function((void *)*pl->arg->v);
*pl->arg->v = 0;
}
for (j=0; j<=pl->count; j++) {
if (!pl->arg[j].v) continue;
for (i = 0; i<=pl->arg[j].c; i++) free(pl->arg[j].v[i]);
free(pl->arg[j].v);
}
free(pl);
}
// Append a new pipeline to function, returning pipeline and pipeline's arg
static struct sh_pipeline *add_pl(struct sh_pipeline **ppl, struct sh_arg **arg)
{
struct sh_pipeline *pl = xzalloc(sizeof(struct sh_pipeline));
if (arg) *arg = pl->arg;
pl->lineno = TT.LINENO;
dlist_add_nomalloc((void *)ppl, (void *)pl);
return pl->end = pl;
}
// Add a line of shell script to a shell function. Returns 0 if finished,
// 1 to request another line of input (> prompt), -1 for syntax err
static int parse_line(char *line, struct sh_pipeline **ppl,
struct double_list **expect)
{
char *start = line, *delete = 0, *end, *s, *ex, done = 0,
*tails[] = {"fi", "done", "esac", "}", "]]", ")", 0};
struct sh_pipeline *pl = *ppl ? (*ppl)->prev : 0, *pl2, *pl3;
struct sh_arg *arg = 0;
long i;
// Resume appending to last statement?
if (pl) {
arg = pl->arg;
// Extend/resume quoted block
if (arg->c<0) {
delete = start = xmprintf("%s%s", arg->v[arg->c = (-arg->c)-1], start);
free(arg->v[arg->c]);
arg->v[arg->c] = 0;
// is a HERE document in progress?
} else if (pl->count != pl->here) {
arg += 1+pl->here;
// Match unquoted EOF.
for (s = line, end = arg->v[arg->c]; *s && *end; s++) {
s += strspn(s, "\\\"'");
if (*s != *end) break;
}
// Add this line, else EOF hit so end HERE document
if (!*s && !*end) {
end = arg->v[arg->c];
arg_add(arg, xstrdup(line));
arg->v[arg->c] = end;
} else {
arg->v[arg->c] = 0;
pl->here++;
}
start = 0;
// Nope, new segment if not self-managing type
} else if (pl->type < 128) pl = 0;
}
// Parse words, assemble argv[] pipelines, check flow control and HERE docs
if (start) for (;;) {
ex = *expect ? (*expect)->prev->data : 0;
// Look for << HERE redirections in completed pipeline segment
if (pl && pl->count == -1) {
pl->count = 0;
arg = pl->arg;
// find arguments of the form [{n}]<<[-] with another one after it
for (i = 0; i<arg->c; i++) {
s = arg->v[i] + redir_prefix(arg->v[i]);
// TODO <<< is funky
// argc[] entries removed from main list? Can have more than one?
if (strcmp(s, "<<") && strcmp(s, "<<-") && strcmp(s, "<<<")) continue;
if (i+1 == arg->c) goto flush;
// Add another arg[] to the pipeline segment (removing/readding to list
// because realloc can move pointer)
dlist_lpop(ppl);
pl = xrealloc(pl, sizeof(*pl) + ++pl->count*sizeof(struct sh_arg));
dlist_add_nomalloc((void *)ppl, (void *)pl);
// queue up HERE EOF so input loop asks for more lines.
arg[pl->count].v = xzalloc(2*sizeof(void *));
arg[pl->count].v[0] = arg->v[++i];
arg[pl->count].v[1] = 0;
arg[pl->count].c = 0;
if (s[2] == '<') pl->here++; // <<< doesn't load more data
}
// Did we just end a function?
if (ex == (void *)1) {
struct sh_function *funky;
// function must be followed by a compound statement for some reason
if ((*ppl)->prev->type != 3) {
s = *(*ppl)->prev->arg->v;
goto flush;
}
// Back up to saved function() statement and create sh_function
free(dlist_lpop(expect));
pl = (void *)(*expect)->data;
funky = xmalloc(sizeof(struct sh_function));
funky->refcount = 1;
funky->name = *pl->arg->v;
*pl->arg->v = (void *)funky;
// Chop out pipeline segments added since saved function
funky->pipeline = pl->next;
pl->next->prev = (*ppl)->prev;
(*ppl)->prev->next = pl->next;
pl->next = *ppl;
(*ppl)->prev = pl;
dlist_terminate(funky->pipeline = add_pl(&funky->pipeline, 0));
funky->pipeline->type = 'f';
// Immature function has matured (meaning cleanup is different)
pl->type = 'F';
free(dlist_lpop(expect));
ex = *expect ? (*expect)->prev->data : 0;
}
pl = 0;
}
if (done) break;
s = 0;
// skip leading whitespace/comment here to know where next word starts
while (isspace(*start)) ++start;
if (*start=='#') while (*start && *start != '\n') ++start;
// Parse next word and detect overflow (too many nested quotes).
if ((end = parse_word(start, 0, 0)) == (void *)1) goto flush;
//dprintf(2, "%d %p %s word=%.*s\n", getpid(), pl, (ex != (void *)1) ? ex : "function", (int)(end-start), end ? start : "");
if (pl && pl->type == 'f' && arg->c == 1 && (end-start!=1 || *start!='(')) {
funky:
// end function segment, expect function body
dlist_add(expect, (void *)pl);
pl = 0;
dlist_add(expect, (void *)1);
dlist_add(expect, 0);
continue;
}
// Is this a new pipeline segment?
if (!pl) pl = add_pl(ppl, &arg);
// Do we need to request another line to finish word (find ending quote)?
if (!end) {
// Save unparsed bit of this line, we'll need to re-parse it.
arg_add(arg, xstrndup(start, strlen(start)));
arg->c = -arg->c;
free(delete);
return 1;
}
// Ok, we have a word. What does it _mean_?
// case/esac parsing is weird (unbalanced parentheses!), handle first
i = (unsigned long)ex>1 && !strcmp(ex, "esac") &&
((pl->type && pl->type != 3) || (*start==';' && end-start>1));
if (i) {
// Premature EOL in type 1 (case x\nin) or 2 (at start or after ;;) is ok
if (end == start) {
if (pl->type==128 && arg->c==2) break; // case x\nin
if (pl->type==129 && (!arg->c || (arg->c==1 && **arg->v==';'))) break;
s = "newline";
goto flush;
}
// type 0 means just got ;; so start new type 2
if (!pl->type) {
// catch "echo | ;;" errors
if (arg->v && arg->v[arg->c] && strcmp(arg->v[arg->c], "&")) goto flush;
if (!arg->c) {
if (pl->prev->type == 2) {
// Add a call to "true" between empty ) ;;
arg_add(arg, xstrdup(":"));
pl = add_pl(ppl, &arg);
}
pl->type = 129;
} else {
// check for here documents
pl->count = -1;
continue;
}
}
// Did we hit end of line or ) outside a function declaration?
// ) is only saved at start of a statement, ends current statement
} else if (end == start || (arg->c && *start == ')' && pl->type!='f')) {
// function () needs both parentheses or neither
if (pl->type == 'f' && arg->c != 1 && arg->c != 3) {
s = "function(";
goto flush;
}
// "for" on its own line is an error.
if (arg->c == 1 && (unsigned long)ex>1 && !memcmp(ex, "do\0A", 4)) {
s = "newline";
goto flush;
}
// Stop at EOL. Discard blank pipeline segment, else end segment
if (end == start) done++;
if (!pl->type && !arg->c) {
free_pipeline(dlist_lpop(ppl));
pl = *ppl ? (*ppl)->prev : 0;
} else pl->count = -1;
continue;
}
// Save word and check for flow control
arg_add(arg, s = xstrndup(start, end-start));
start = end;
// Second half of case/esac parsing
if (i) {
// type 1 (128): case x [\n] in
if (pl->type==128) {
if (arg->c==2 && strchr("()|;&", *s)) goto flush;
if (arg->c==3) {
if (strcmp(s, "in")) goto flush;
pl->type = 1;
(pl = add_pl(ppl, &arg))->type = 129;
}
continue;
// type 2 (129): [;;] [(] pattern [|pattern...] )
} else {
// can't start with line break or ";;" or "case ? in ;;" without ")"
if (*s==';') {
if (arg->c>1 || (arg->c==1 && pl->prev->type==1)) goto flush;
} else pl->type = 2;
i = arg->c - (**arg->v==';' && arg->v[0][1]);
if (i==1 && !strcmp(s, "esac")) {
// esac right after "in" or ";;" ends block, fall through
if (arg->c>1) {
arg->v[1] = 0;
pl = add_pl(ppl, &arg);
arg_add(arg, s);
} else pl->type = 0;
} else {
if (arg->c>1) i -= *arg->v[1]=='(';
if (i>0 && ((i&1)==!!strchr("|)", *s) || strchr(";(", *s)))
goto flush;
if (*s=='&' || !strcmp(s, "||")) goto flush;
if (*s==')') pl = add_pl(ppl, &arg);
continue;
}
}
}
// Are we starting a new [function] name [()] definition
if (!pl->type || pl->type=='f') {
if (!pl->type && arg->c==1 && !strcmp(s, "function")) {
free(arg->v[--arg->c]);
arg->v[arg->c] = 0;
pl->type = 'f';
continue;
} else if (arg->c==2 && !strcmp(s, "(")) pl->type = 'f';
}
// one or both of [function] name[()]
if (pl->type=='f') {
if (arg->v[0][strcspn(*arg->v, "\"'`><;|&$")]) {
s = *arg->v;
goto flush;
}
if (arg->c == 2 && strcmp(s, "(")) goto flush;
if (arg->c == 3) {
if (strcmp(s, ")")) goto flush;
goto funky;
}
continue;
// is it a line break token?
} else if (strchr(";|&", *s) && strncmp(s, "&>", 2)) {
arg->c--;
// treat ; as newline so we don't have to check both elsewhere.
if (!strcmp(s, ";")) {
arg->v[arg->c] = 0;
free(s);
s = 0;
// TODO can't have ; between "for i" and in or do. (Newline yes, ; no. Why?)
if (!arg->c && (unsigned long)ex>1 && !memcmp(ex, "do\0C", 4)) continue;
// ;; and friends only allowed in case statements
} else if (*s == ';') goto flush;
// flow control without a statement is an error
if (!arg->c) goto flush;
pl->count = -1;
continue;
// a for/select must have at least one additional argument on same line
} else if ((unsigned long)ex>1 && !memcmp(ex, "do\0A", 4)) {
// Sanity check and break the segment
if (strncmp(s, "((", 2) && *varend(s)) goto flush;
pl->count = -1;
(*expect)->prev->data = "do\0C";
continue;
// flow control is the first word of a pipeline segment
} else if (arg->c>1) continue;
// Do we expect something that _must_ come next? (no multiple statements)
if ((unsigned long)ex>1) {
// The "test" part of for/select loops can have (at most) one "in" line,
// for {((;;))|name [in...]} do
if (!memcmp(ex, "do\0C", 4)) {
if (strcmp(s, "do")) {
// can only have one "in" line between for/do, but not with for(())
if (pl->prev->type == 's') goto flush;
if (!strncmp(pl->prev->arg->v[1], "((", 2)) goto flush;
else if (strcmp(s, "in")) goto flush;
pl->type = 's';
continue;
}
}
}
// start of a new block?
// for/select/case require var name on same line, can't break segment yet
if (!strcmp(s, "for") || !strcmp(s, "select") || !strcmp(s, "case")) {
// TODO why !pl->type here
if (!pl->type) pl->type = (*s == 'c') ? 128 : 1;
dlist_add(expect, (*s == 'c') ? "esac" : "do\0A");
continue;
}
end = 0;
if (!strcmp(s, "if")) end = "then";
else if (!strcmp(s, "while") || !strcmp(s, "until")) end = "do\0B";
else if (!strcmp(s, "{")) end = "}";
else if (!strcmp(s, "[[")) end = "]]";
else if (!strcmp(s, "(")) end = ")";
// Expecting NULL means a statement: I.E. any otherwise unrecognized word
if (!ex && *expect) free(dlist_lpop(expect));
// Did we start a new statement
if (end) {
pl->type = 1;
// Only innermost statement needed in { { { echo ;} ;} ;} and such
if (*expect && !(*expect)->prev->data) free(dlist_lpop(expect));
// if can't end a statement here skip next few tests
} else if ((unsigned long)ex<2);
// If we got here we expect a specific word to end this block: is this it?
else if (!strcmp(s, ex)) {
// can't "if | then" or "while && do", only ; & or newline works
if (strcmp(pl->prev->arg->v[pl->prev->arg->c] ? : "&", "&")) goto flush;
// consume word, record block end location in earlier !0 type blocks
free(dlist_lpop(expect));
if (3 == (pl->type = anystr(s, tails) ? 3 : 2)) {
for (i = 0, pl2 = pl3 = pl; (pl2 = pl2->prev);) {
if (pl2->type == 3) i++;
else if (pl2->type) {
if (!i) {
if (pl2->type == 2) {
pl2->end = pl3;
pl3 = pl2;
} else pl2->end = pl;
}
if (pl2->type == 1 && --i<0) break;
}
}
}
// if it's a multipart block, what comes next?
if (!strcmp(s, "do")) end = "done";
else if (!strcmp(s, "then")) end = "fi\0A";
// fi could have elif, which queues a then.
} else if (!strcmp(ex, "fi")) {
if (!strcmp(s, "elif")) {
free(dlist_lpop(expect));
end = "then";
// catch duplicate else while we're here
} else if (!strcmp(s, "else")) {
if (ex[3] != 'A') {
s = "2 else";
goto flush;
}
free(dlist_lpop(expect));
end = "fi\0B";
}
}
// Queue up the next thing to expect, all preceded by a statement
if (end) {
if (!pl->type) pl->type = 2;
dlist_add(expect, end);
if (!anystr(end, tails)) dlist_add(expect, 0);
pl->count = -1;
}
// syntax error check: these can't be the first word in an unexpected place
if (!pl->type && anystr(s, (char *[]){"then", "do", "esac", "}", "]]", ")",
"done", "fi", "elif", "else", 0})) goto flush;
}
free(delete);
// ignore blank and comment lines
if (!*ppl) return 0;
// TODO <<< has no parsing impact, why play with it here at all?
// advance past <<< arguments (stored as here documents, but no new input)
pl = (*ppl)->prev;
while (pl->count<pl->here && pl->arg[pl->count].c<0)
pl->arg[pl->count++].c = 0;
// return if HERE document pending or more flow control needed to complete
if (*expect) return 1;
if (*ppl && pl->count != pl->here) return 1;
if (pl->arg->v[pl->arg->c] && strcmp(pl->arg->v[pl->arg->c], "&")) return 1;
// Don't need more input, can start executing.
dlist_terminate(*ppl);
return 0;
flush:
if (s) syntax_err(s);
llist_traverse(*ppl, free_pipeline);
*ppl = 0;
llist_traverse(*expect, free);
*expect = 0;
return 0-!!s;
}
// Find + and - jobs. Returns index of plus, writes minus to *minus
int find_plus_minus(int *minus)
{
long long when, then;
int i, plus;
if (minus) *minus = 0;
for (then = i = plus = 0; i<TT.jobs.c; i++) {
if ((when = ((struct sh_process *)TT.jobs.v[i])->when) > then) {
then = when;
if (minus) *minus = plus;
plus = i;
}
}
return plus;
}
char is_plus_minus(int i, int plus, int minus)
{
return (i == plus) ? '+' : (i == minus) ? '-' : ' ';
}
// We pass in dash to avoid looping over every job each time
char *show_job(struct sh_process *pp, char dash)
{
char *s = "Run", *buf = 0;
int i, j, len, len2;
// TODO Terminated (Exited)
if (pp->exit<0) s = "Stop";
else if (pp->exit>126) s = "Kill";
else if (pp->exit>0) s = "Done";
for (i = len = len2 = 0;; i++) {
len += snprintf(buf, len2, "[%d]%c %-6s", pp->job, dash, s);
for (j = 0; j<pp->raw->c; j++)
len += snprintf(buf, len2, " %s"+!j, pp->raw->v[j]);
if (!i) buf = xmalloc(len2 = len+1);
else break;
}
return buf;
}
// Wait for pid to exit and remove from jobs table, returning process or 0.
struct sh_process *wait_job(int pid, int nohang)
{
struct sh_process *pp = pp;
int ii, status, minus, plus;
if (TT.jobs.c<1) return 0;
for (;;) {
errno = 0;
if (1>(pid = waitpid(pid, &status, nohang ? WNOHANG : 0))) {
if (!nohang && errno==EINTR && !toys.signal) continue;
return 0;
}
for (ii = 0; ii<TT.jobs.c; ii++) {
pp = (void *)TT.jobs.v[ii];
if (pp->pid == pid) break;
}
if (ii == TT.jobs.c) continue;
if (pid<1) return 0;
if (!WIFSTOPPED(status) && !WIFCONTINUED(status)) break;
}
plus = find_plus_minus(&minus);
memmove(TT.jobs.v+ii, TT.jobs.v+ii+1, (TT.jobs.c--)-ii);
pp->exit = WIFEXITED(status) ? WEXITSTATUS(status) : WTERMSIG(status)+128;
pp->dash = is_plus_minus(ii, plus, minus);
return pp;
}
// wait for every process in a pipeline to end
static int wait_pipeline(struct sh_process *pp)
{
int rc = 0;
for (dlist_terminate(pp); pp; pp = pp->next) {
if (pp->pid) {
// TODO job control: not xwait, handle EINTR ourselves and check signals
pp->exit = xwaitpid(pp->pid);
pp->pid = 0;
}
// TODO handle set -o pipefail here
rc = (pp->flags&PFLAG_NOT) ? !pp->exit : pp->exit;
}
while ((pp = wait_job(-1, 1)) && (TT.options&FLAG_i)) {
char *s = show_job(pp, pp->dash);
dprintf(2, "%s\n", s);
free(s);
}
return rc;
}
// Print prompt to stderr, parsing escapes
// Truncated to 4k at the moment, waiting for somebody to complain.
static void do_prompt(char *prompt)
{
char *s, *ss, c, cc, *pp = toybuf;
int len, ll;
if (!prompt) return;
while ((len = sizeof(toybuf)-(pp-toybuf))>0 && *prompt) {
c = *(prompt++);
if (c=='!') {
if (*prompt=='!') prompt++;
else {
pp += snprintf(pp, len, "%u", TT.LINENO);
continue;
}
} else if (c=='\\') {
cc = *(prompt++);
if (!cc) {
*pp++ = c;
break;
}
// \nnn \dD{}hHjlstT@AuvVwW!#$
// Ignore bash's "nonprintable" hack; query our cursor position instead.
if (cc=='[' || cc==']') continue;
else if (cc=='$') *pp++ = getuid() ? '$' : '#';
else if (cc=='h' || cc=='H') {
*pp = 0;
gethostname(pp, len);
pp[len-1] = 0;
if (cc=='h' && (s = strchr(pp, '.'))) *s = 0;
pp += strlen(pp);
} else if (cc=='s') {
s = getbasename(*toys.argv);
while (*s && len--) *pp++ = *s++;
} else if (cc=='w') {
if ((s = getvar("PWD"))) {
if ((ss = getvar("HOME")) && strstart(&s, ss)) {
*pp++ = '~';
if (--len && *s!='/') *pp++ = '/';
len--;
}
if (len>0) {
ll = strlen(s);
pp = stpncpy(pp, s, ll>len ? len : ll);
}
}
} else if (!(c = unescape(cc))) {
*pp++ = '\\';
if (--len) *pp++ = c;
} else *pp++ = c;
} else *pp++ = c;
}
len = pp-toybuf;
if (len>=sizeof(toybuf)) len = sizeof(toybuf);
writeall(2, toybuf, len);
}
// returns NULL for EOF, 1 for invalid, else null terminated string.
static char *get_next_line(FILE *ff, int prompt)
{
char *new;
int len, cc;
if (!ff) {
char ps[16];
sprintf(ps, "PS%d", prompt);
do_prompt(getvar(ps));
}
// TODO what should ctrl-C do? (also in "select")
// TODO line editing/history, should set $COLUMNS $LINES and sigwinch update
// TODO: after first EINTR returns closed?
// TODO: ctrl-z during script read having already read partial line,
// SIGSTOP and SIGTSTP need SA_RESTART, but child proc should stop
// TODO if (!isspace(*new)) add_to_history(line);
// TODO: embedded nul bytes need signaling for the "tried to run binary" test.
for (new = 0, len = 0;;) {
errno = 0;
if (!(cc = getc(ff ? : stdin))) {
if (TT.LINENO) continue;
free(new);
return (char *)1;
}
if (cc<0) {
if (errno == EINTR) continue;
break;
}
if (!(len&63)) new = xrealloc(new, len+65);
if (cc == '\n') break;
new[len++] = cc;
}
if (new) new[len] = 0;
return new;
}
/*
TODO: "echo | read i" is backgroundable with ctrl-Z despite read = builtin.
probably have to inline run_command here to do that? Implicit ()
also "X=42 | true; echo $X" doesn't get X.
I.E. run_subshell() here sometimes? (But when?)
TODO: bash supports "break &" and "break > file". No idea why.
TODO If we just started a new pipeline, implicit parentheses (subshell)
TODO can't free sh_process delete until ready to dispose else no debug output
TODO: a | b | c needs subshell for builtins?
- anything that can produce output
- echo declare dirs
(a; b; c) like { } but subshell
when to auto-exec? ps vs sh -c 'ps' vs sh -c '(ps)'
*/
// run a parsed shell function. Handle flow control blocks and characters,
// setup pipes and block redirection, break/continue, call builtins, functions,
// vfork/exec external commands. Return when out of input.
static void run_lines(void)
{
char *ctl, *s, *ss, **vv;
struct sh_process *pp, *pplist = 0; // processes piping into current level
long i, j, k;
// iterate through pipeline segments
for (;;) {
if (!TT.ff->pl) {
if (!end_function(1)) break;
goto advance;
}
ctl = TT.ff->pl->end->arg->v[TT.ff->pl->end->arg->c];
s = *TT.ff->pl->arg->v;
ss = TT.ff->pl->arg->v[1];
//dprintf(2, "%d s=%s ss=%s ctl=%s type=%d pl=%p ff=%p\n", getpid(), (TT.ff->pl->type == 'F') ? ((struct sh_function *)s)->name : s, ss, ctl, TT.ff->pl->type, TT.ff->pl, TT.ff);
if (!pplist) TT.hfd = 10;
// Skip disabled blocks, handle pipes and backgrounding
if (TT.ff->pl->type<2) {
if (!TT.ff->blk->run) {
TT.ff->pl = TT.ff->pl->end->next;
continue;
}
if (TT.options&OPT_x) {
unsigned lineno;
char *ss, *ps4 = getvar("PS4");
// duplicate first char of ps4 call depth times
if (ps4 && *ps4) {
j = getutf8(ps4, k = strlen(ps4), 0);
ss = xmalloc(TT.srclvl*j+k+1);
for (k = 0; k<TT.srclvl; k++) memcpy(ss+k*j, ps4, j);
strcpy(ss+k*j, ps4+j);
// show saved line number from function, not next to read
lineno = TT.LINENO;
TT.LINENO = TT.ff->pl->lineno;
do_prompt(ss);
TT.LINENO = lineno;
free(ss);
// TODO resolve variables
ss = pl2str(TT.ff->pl, 1);
dprintf(2, "%s\n", ss);
free(ss);
}
}
// pipe data into and out of this segment, I.E. leading/trailing |
unredirect(TT.ff->blk->urd);
TT.ff->blk->urd = 0;
TT.ff->blk->pipe = 0;
// Consume pipe from previous segment as stdin.
if (TT.ff->blk->pout != -1) {
TT.ff->blk->pipe++;
if (save_redirect(&TT.ff->blk->urd, TT.ff->blk->pout, 0)) break;
close(TT.ff->blk->pout);
TT.ff->blk->pout = -1;
}
// Create output pipe and save next process's stdin in pout
if (ctl && *ctl == '|' && ctl[1] != '|') {
int pipes[2] = {-1, -1};
TT.ff->blk->pipe++;
if (pipe(pipes)) {
perror_msg("pipe");
break;
}
if (save_redirect(&TT.ff->blk->urd, pipes[1], 1)) {
close(pipes[0]);
close(pipes[1]);
break;
}
if (pipes[1] != 1) close(pipes[1]);
fcntl(TT.ff->blk->pout = *pipes, F_SETFD, FD_CLOEXEC);
if (ctl[1] == '&') save_redirect(&TT.ff->blk->urd, 1, 2);
}
}
// Is this an executable segment?
if (!TT.ff->pl->type) {
// Is it a flow control jump? These aren't handled as normal builtins
// because they move *pl to other pipeline segments which is local here.
if (!strcmp(s, "break") || !strcmp(s, "continue")) {
// How many layers to peel off?
i = ss ? atol(ss) : 0;
if (i<1) i = 1;
if (TT.ff->blk->next && TT.ff->pl->arg->c<3
&& (!ss || !ss[strspn(ss,"0123456789")]))
{
while (i && TT.ff->blk->next)
if (TT.ff->blk->middle && !strcmp(*TT.ff->blk->middle->arg->v, "do")
&& !--i && *s=='c') TT.ff->pl = TT.ff->blk->start;
else TT.ff->pl = pop_block();
}
if (i) {
syntax_err(s);
break;
}
// Parse and run next command, saving resulting process
} else if ((pp = run_command()))
dlist_add_nomalloc((void *)&pplist, (void *)pp);
// Start of flow control block?
} else if (TT.ff->pl->type == 1) {
// TODO test cat | {thingy} is new PID: { is ( for |
// perform/save trailing redirects
pp = expand_redir(TT.ff->pl->end->arg, 1, TT.ff->blk->urd);
TT.ff->blk->urd = pp->urd;
pp->urd = 0;
if (pp->arg.c) syntax_err(*pp->arg.v);
llist_traverse(pp->delete, llist_free_arg);
pp->delete = 0;
if (pp->exit || pp->arg.c) {
free(pp);
toys.exitval = 1;
break;
}
add_block();
// TODO test background a block: { abc; } &
// If we spawn a subshell, pass data off to child process
if (TT.ff->blk->pipe || !strcmp(s, "(") || (ctl && !strcmp(ctl, "&"))) {
if (!(pp->pid = run_subshell(0, -1))) {
// zap forked child's cleanup context and advance to next statement
pplist = 0;
while (TT.ff->blk->next) TT.ff->blk = TT.ff->blk->next;
TT.ff->blk->pout = -1;
TT.ff->blk->urd = 0;
TT.ff->pl = TT.ff->next->pl->next;
continue;
}
TT.ff->pl = TT.ff->pl->end;
pop_block();
dlist_add_nomalloc((void *)&pplist, (void *)pp);
// handle start of block in this process
} else {
free(pp);
// What flow control statement is this?
// {/} if/then/elif/else/fi, while until/do/done - no special handling
// for/select/do/done: populate blk->farg with expanded args (if any)
if (!strcmp(s, "for") || !strcmp(s, "select")) {
if (TT.ff->blk->loop);
else if (!strncmp(TT.ff->blk->fvar = ss, "((", 2)) {
TT.ff->blk->loop = 1;
dprintf(2, "TODO skipped init for((;;)), need math parser\n");
// in LIST
} else if (TT.ff->pl->next->type == 's') {
for (i = 1; i<TT.ff->pl->next->arg->c; i++)
if (expand_arg(&TT.ff->blk->farg, TT.ff->pl->next->arg->v[i],
0, &TT.ff->blk->fdelete)) break;
if (i != TT.ff->pl->next->arg->c) TT.ff->pl = pop_block();
// in without LIST. (This expansion can't return error.)
} else expand_arg(&TT.ff->blk->farg, "\"$@\"", 0,
&TT.ff->blk->fdelete);
// TODO: ls -C style output
if (*s == 's') for (i = 0; i<TT.ff->blk->farg.c; i++)
dprintf(2, "%ld) %s\n", i+1, TT.ff->blk->farg.v[i]);
// TODO: bash man page says it performs <(process substituion) here?!?
} else if (!strcmp(s, "case")) {
TT.ff->blk->fvar = expand_one_arg(ss, NO_NULL, &TT.ff->blk->fdelete);
if (!TT.ff->blk->fvar) break;
}
// TODO [[/]] ((/)) function/}
}
// gearshift from block start to block body (end of flow control test)
} else if (TT.ff->pl->type == 2) {
int match, err;
TT.ff->blk->middle = TT.ff->pl;
// ;; end, ;& continue through next block, ;;& test next block
if (!strcmp(*TT.ff->blk->start->arg->v, "case")) {
if (!strcmp(s, ";;")) {
while (TT.ff->pl->type!=3) TT.ff->pl = TT.ff->pl->end;
continue;
} else if (strcmp(s, ";&")) {
struct sh_arg arg = {0}, arg2 = {0};
for (err = 0, vv = 0;;) {
if (!vv) {
vv = TT.ff->pl->arg->v + (**TT.ff->pl->arg->v == ';');
if (!*vv) {
// TODO syntax err if not type==3, catch above
TT.ff->pl = TT.ff->pl->next;
break;
} else vv += **vv == '(';
}
arg.c = arg2.c = 0;
if ((err = expand_arg_nobrace(&arg, *vv++, NO_SPLIT,
&TT.ff->blk->fdelete, &arg2))) break;
s = arg.c ? *arg.v : "";
match = wildcard_match(TT.ff->blk->fvar, s, &arg2, 0);
if (match>=0 && !s[match]) break;
else if (**vv++ == ')') {
vv = 0;
if ((TT.ff->pl = TT.ff->pl->end)->type!=2) break;
}
}
free(arg.v);
free(arg2.v);
if (err) break;
if (TT.ff->pl->type==3) continue;
}
// Handle if/else/elif statement
} else if (!strcmp(s, "then"))
TT.ff->blk->run = TT.ff->blk->run && !toys.exitval;
else if (!strcmp(s, "else") || !strcmp(s, "elif"))
TT.ff->blk->run = !TT.ff->blk->run;
// Loop
else if (!strcmp(s, "do")) {
struct sh_blockstack *blk = TT.ff->blk;
ss = *blk->start->arg->v;
if (!strcmp(ss, "while")) blk->run = blk->run && !toys.exitval;
else if (!strcmp(ss, "until")) blk->run = blk->run && toys.exitval;
else if (!strcmp(ss, "select")) {
if (!(ss = get_next_line(0, 3)) || ss==(void *)1) {
TT.ff->pl = pop_block();
printf("\n");
} else {
match = atoi(ss);
free(ss);
if (!*ss) {
TT.ff->pl = blk->start;
continue;
} else setvarval(blk->fvar, (match<1 || match>blk->farg.c)
? "" : blk->farg.v[match-1]);
}
} else if (blk->loop >= blk->farg.c) TT.ff->pl = pop_block();
else if (!strncmp(blk->fvar, "((", 2)) {
dprintf(2, "TODO skipped running for((;;)), need math parser\n");
} else setvarval(blk->fvar, blk->farg.v[blk->loop++]);
}
// end of block
} else if (TT.ff->pl->type == 3) {
// If we end a block we're not in, exit subshell
if (!TT.ff->blk->next) xexit();
// repeating block?
if (TT.ff->blk->run && !strcmp(s, "done")) {
TT.ff->pl = TT.ff->blk->middle;
continue;
}
// cleans up after trailing redirections/pipe
pop_block();
// declare a shell function
} else if (TT.ff->pl->type == 'F') {
struct sh_function *funky = (void *)*TT.ff->pl->arg->v;
// TODO binary search
for (i = 0; i<TT.funcslen; i++)
if (!strcmp(TT.functions[i]->name, funky->name)) break;
if (i == TT.funcslen) {
struct sh_arg arg = {(void *)TT.functions, TT.funcslen};
arg_add(&arg, (void *)funky); // TODO possibly an expand@31 function?
TT.functions = (void *)arg.v;
TT.funcslen++;
} else {
free_function(TT.functions[i]);
TT.functions[i] = funky;
}
TT.functions[i]->refcount++;
}
// Three cases: 1) background & 2) pipeline | 3) last process in pipeline ;
// If we ran a process and didn't pipe output, background or wait for exit
if (pplist && TT.ff->blk->pout == -1) {
if (ctl && !strcmp(ctl, "&")) {
if (!TT.jobs.c) TT.jobcnt = 0;
pplist->job = ++TT.jobcnt;
arg_add(&TT.jobs, (void *)pplist);
if (TT.options&FLAG_i) dprintf(2, "[%u] %u\n", pplist->job,pplist->pid);
} else {
toys.exitval = wait_pipeline(pplist);
llist_traverse(pplist, (void *)free_process);
}
pplist = 0;
}
advance:
// for && and || skip pipeline segment(s) based on return code
if (!TT.ff->pl->type || TT.ff->pl->type == 3) {
for (;;) {
ctl = TT.ff->pl->arg->v[TT.ff->pl->arg->c];
if (!ctl || strcmp(ctl, toys.exitval ? "&&" : "||")) break;
if ((TT.ff->pl = TT.ff->pl->next)->type) TT.ff->pl = TT.ff->pl->end;
}
}
TT.ff->pl = TT.ff->pl->next;
}
// clean up any unfinished stuff
if (pplist) {
toys.exitval = wait_pipeline(pplist);
llist_traverse(pplist, (void *)free_process);
}
// exit source context (and function calls on syntax err)
while (end_function(0));
}
// set variable
static struct sh_vars *initvar(char *name, char *val)
{
return addvar(xmprintf("%s=%s", name, val ? val : ""), TT.ff);
}
static struct sh_vars *initvardef(char *name, char *val, char *def)
{
return initvar(name, (!val || !*val) ? def : val);
}
// export existing "name" or assign/export name=value string (making new copy)
static void set_varflags(char *str, unsigned set_flags, unsigned unset_flags)
{
struct sh_vars *shv = 0;
struct sh_fcall *ff;
char *s;
// Make sure variable exists and is updated
if (strchr(str, '=')) shv = setvar(xstrdup(str));
else if (!(shv = findvar(str, &ff))) {
if (!set_flags) return;
shv = addvar(str = xmprintf("%s=", str), TT.ff->prev);
shv->flags = VAR_WHITEOUT;
} else if (shv->flags&VAR_WHITEOUT) shv->flags |= VAR_EXPORT;
if (!shv || (shv->flags&VAR_EXPORT)) return;
// Resolve magic for export (bash bug compatibility, really should be dynamic)
if (shv->flags&VAR_MAGIC) {
s = shv->str;
shv->str = xmprintf("%.*s=%s", (int)(varend(str)-str), str, getvar(str));
if (!(shv->flags&VAR_NOFREE)) free(s);
else shv->flags ^= VAR_NOFREE;
}
shv->flags |= set_flags;
shv->flags &= ~unset_flags;
}
static void export(char *str)
{
set_varflags(str, VAR_EXPORT, 0);
}
FILE *fpathopen(char *name)
{
struct string_list *sl = 0;
FILE *f = fopen(name, "r");
char *pp = getvar("PATH") ? : _PATH_DEFPATH;
if (!f) {
for (sl = find_in_path(pp, name); sl; free(llist_pop(&sl)))
if ((f = fopen(sl->str, "r"))) break;
if (sl) llist_traverse(sl, free);
}
return f;
}
// Read script input and execute lines, with or without prompts
int do_source(char *name, FILE *ff)
{
struct sh_pipeline *pl = 0;
struct double_list *expect = 0;
unsigned lineno = TT.LINENO, more = 0, wc;
int cc, ii;
char *new;
if (++TT.recursion>(50+200*CFG_TOYBOX_FORK)) {
error_msg("recursive occlusion");
goto end;
}
if (name) TT.ff->omnom = name;
// TODO fix/catch NONBLOCK on input?
// TODO when DO we reset lineno? (!LINENO means \0 returns 1)
// when do we NOT reset lineno? Inherit but preserve perhaps? newline in $()?
if (!name) TT.LINENO = 0;
do {
if ((void *)1 == (new = get_next_line(ff, more+1))) goto is_binary;
//dprintf(2, "%d getline from %p %s\n", getpid(), ff, new); debug_show_fds();
// did we exec an ELF file or something?
if (!TT.LINENO++ && name && new) {
// A shell script's first line has no high bytes that aren't valid utf-8.
for (ii = 0; new[ii]>6 && 0<(cc = utf8towc(&wc, new+ii, 4)); ii += cc);
if (new[ii]) {
is_binary:
if (name) error_msg("'%s' is binary", name); // TODO syntax_err() exit?
if (new != (void *)1) free(new);
new = 0;
}
}
// TODO: source <(echo 'echo hello\') vs source <(echo -n 'echo hello\')
// prints "hello" vs "hello\"
// returns 0 if line consumed, command if it needs more data
more = parse_line(new ? : " ", &pl, &expect);
free(new);
if (more==1) {
if (!new) {
if (!ff) syntax_err("unexpected end of file");
} else continue;
} else if (!more && pl) {
TT.ff->pl = pl;
run_lines();
} else more = 0;
llist_traverse(pl, free_pipeline);
pl = 0;
llist_traverse(expect, free);
expect = 0;
} while (new);
if (ff) fclose(ff);
if (!name) TT.LINENO = lineno;
end:
TT.recursion--;
return more;
}
// On nommu we had to exec(), so parent environment is passed via a pipe.
static void nommu_reentry(void)
{
struct stat st;
int ii, pid, ppid, len;
unsigned long ll;
char *s = 0;
FILE *fp;
// Sanity check
if (!fstat(254, &st) && S_ISFIFO(st.st_mode)) {
for (ii = len = 0; (s = environ[ii]); ii++) {
if (*s!='@') continue;
sscanf(s, "@%u,%u%n", &pid, &ppid, &len);
break;
}
}
if (!s || s[len] || pid!=getpid() || ppid!=getppid()) error_exit(0);
// TODO signal setup before this so fscanf can't EINTR.
// TODO marshall TT.jobcnt TT.funcslen: child needs jobs and function list
// Marshall magics: $SECONDS $- $LINENO $$ $!
if (5!=fscanf(fp = fdopen(254, "r"), "%lld %u %u %u %u%*[^\n]", &TT.SECONDS,
&TT.options, &TT.LINENO, &TT.pid, &TT.bangpid)) error_exit(0);
// Read named variables: type, len, var=value\0
for (;;) {
len = ll = 0;
(void)fscanf(fp, "%u %lu%*[^\n]", &len, &ll);
fgetc(fp); // Discard the newline fscanf didn't eat.
if (!len) break;
(s = xmalloc(len+1))[len] = 0;
for (ii = 0; ii<len; ii += pid)
if (1>(pid = fread(s+ii, 1, len-ii, fp))) error_exit(0);
set_varflags(s, ll, 0);
}
// Perform subshell command(s)
do_source(0, fp);
xexit();
}
// init locals, sanitize environment, handle nommu subshell handoff
static void subshell_setup(void)
{
int ii, from, uid = getuid();
struct passwd *pw = getpwuid(uid);
char *s, *ss, *magic[] = {"SECONDS", "RANDOM", "LINENO", "GROUPS", "BASHPID",
"EPOCHREALTIME", "EPOCHSECONDS"},
*readonly[] = {xmprintf("EUID=%d", geteuid()), xmprintf("UID=%d", uid),
xmprintf("PPID=%d", getppid())};
struct sh_vars *shv;
struct utsname uu;
// Initialize magic and read only local variables
for (ii = 0; ii<ARRAY_LEN(magic) && (s = magic[ii]); ii++)
initvar(s, "")->flags = VAR_MAGIC+VAR_INT*('G'!=*s)+VAR_READONLY*('B'==*s);
for (ii = 0; ii<ARRAY_LEN(readonly); ii++)
addvar(readonly[ii], TT.ff)->flags = VAR_READONLY|VAR_INT;
// Add local variables that can be overwritten
initvar("PATH", _PATH_DEFPATH);
if (!pw) pw = (void *)toybuf; // first use, so still zeroed
sprintf(toybuf+1024, "%u", uid);
initvardef("HOME", pw->pw_dir, "/");
initvardef("SHELL", pw->pw_shell, "/bin/sh");
initvardef("USER", pw->pw_name, toybuf+1024);
initvardef("LOGNAME", pw->pw_name, toybuf+1024);
gethostname(toybuf, sizeof(toybuf)-1);
initvar("HOSTNAME", toybuf);
uname(&uu);
initvar("HOSTTYPE", uu.machine);
sprintf(toybuf, "%s-unknown-linux", uu.machine);
initvar("MACHTYPE", toybuf);
initvar("OSTYPE", uu.sysname);
// sprintf(toybuf, "%s-toybox", TOYBOX_VERSION);
// initvar("BASH_VERSION", toybuf); TODO
initvar("OPTERR", "1"); // TODO: test if already exported?
if (readlink0("/proc/self/exe", s = toybuf, sizeof(toybuf))||(s=getenv("_")))
initvar("BASH", s);
initvar("PS2", "> ");
initvar("PS3", "#? ");
initvar("PS4", "+ ");
// Ensure environ copied and toys.envc set, and clean out illegal entries
for (from = 0; (s = environ[from]); from++) {
if (*varend(s) != '=') continue;
if (!(shv = findvar(s, 0))) addvar(s, TT.ff)->flags = VAR_EXPORT|VAR_NOFREE;
else if (shv->flags&VAR_READONLY) continue;
else {
if (!(shv->flags&VAR_NOFREE)) {
free(shv->str);
shv->flags ^= VAR_NOFREE;
}
shv->flags |= VAR_EXPORT;
shv->str = s;
}
cache_ifs(s, TT.ff);
}
// set/update PWD
do_source(0, fmemopen("cd .", 4, "r"));
// set _ to path to this shell
s = toys.argv[0];
ss = 0;
if (!strchr(s, '/')) {
if ((ss = getcwd(0, 0))) {
s = xmprintf("%s/%s", ss, s);
free(ss);
ss = s;
} else if (*toybuf) s = toybuf; // from /proc/self/exe
}
setvarval("_", s)->flags |= VAR_EXPORT;
free(ss);
// TODO: this is in pipe, not environment
if (!(ss = getvar("SHLVL"))) export("SHLVL=1"); // Bash 5.0
else {
char buf[16];
sprintf(buf, "%u", atoi(ss+6)+1);
setvarval("SHLVL", buf)->flags |= VAR_EXPORT;
}
}
void sh_main(void)
{
char *cc = 0;
FILE *ff;
//unsigned uu; dprintf(2, "%d main", getpid()); for (uu = 0; toys.argv[uu]; uu++) dprintf(2, " %s", toys.argv[uu]); dprintf(2, "\n");
signal(SIGPIPE, SIG_IGN);
TT.options = OPT_B;
TT.pid = getpid();
srandom(TT.SECONDS = millitime());
// TODO euid stuff?
// TODO login shell?
// TODO read profile, read rc
// if (!FLAG(noprofile)) { }
// If not reentering, figure out if this is an interactive shell.
if (toys.stacktop) {
cc = TT.sh.c;
if (!FLAG(c)) {
if (toys.optc==1) toys.optflags |= FLAG_s;
if (FLAG(s) && isatty(0)) toys.optflags |= FLAG_i;
}
if (toys.optc>1) {
toys.optargs++;
toys.optc--;
}
TT.options |= toys.optflags&0xff;
}
// Create initial function context
call_function();
TT.ff->arg.v = toys.optargs;
TT.ff->arg.c = toys.optc;
TT.ff->ifs = " \t\n";
// Set up environment variables.
// Note: can call run_command() which blanks argument sections of TT and this,
// so parse everything we need from shell command line before here.
if (CFG_TOYBOX_FORK || toys.stacktop) subshell_setup(); // returns
else nommu_reentry(); // does not return
if (TT.options&FLAG_i) {
if (!getvar("PS1")) setvarval("PS1", getpid() ? "\\$ " : "# ");
// TODO Set up signal handlers and grab control of this tty.
// ^C SIGINT ^\ SIGQUIT ^Z SIGTSTP SIGTTIN SIGTTOU SIGCHLD
// setsid(), setpgid(), tcsetpgrp()...
xsignal(SIGINT, SIG_IGN);
}
if (cc) ff = fmemopen(cc, strlen(cc), "r");
else if (TT.options&FLAG_s) ff = (TT.options&FLAG_i) ? 0 : stdin;
else if (!(ff = fpathopen(*toys.optargs))) perror_exit_raw(*toys.optargs);
// Read and execute lines from file
if (do_source(cc ? : *toys.optargs, ff))
error_exit("%u:unfinished line"+3*!TT.LINENO, TT.LINENO);
}
// TODO: ./blah.sh one two three: put one two three in scratch.arg
/********************* shell builtin functions *************************/
#define FOR_cd
#include "generated/flags.h"
void cd_main(void)
{
char *from, *to = 0, *dd = *toys.optargs ? : (getvar("HOME") ? : "/"),
*pwd = FLAG(P) ? 0 : getvar("PWD"), *zap = 0;
struct stat st1, st2;
// TODO: CDPATH? Really?
// For cd - use $OLDPWD as destination directory
if (!strcmp(dd, "-") && (!(dd = getvar("OLDPWD")) || !*dd))
return perror_msg("No $OLDPWD");
if (*dd == '/') pwd = 0;
// Did $PWD move out from under us?
if (pwd && !stat(".", &st1))
if (stat(pwd, &st2) || st1.st_dev!=st2.st_dev || st1.st_ino!=st2.st_ino)
pwd = 0;
// Handle logical relative path
if (pwd) {
zap = xmprintf("%s/%s", pwd, dd);
// cancel out . and .. in the string
for (from = to = zap; *from;) {
if (*from=='/' && from[1]=='/') from++;
else if (*from!='/' || from[1]!='.') *to++ = *from++;
else if (!from[2] || from[2]=='/') from += 2;
else if (from[2]=='.' && (!from[3] || from[3]=='/')) {
from += 3;
while (to>zap && *--to != '/');
} else *to++ = *from++;
}
if (to == zap) to++;
if (to-zap>1 && to[-1]=='/') to--;
*to = 0;
}
// If logical chdir doesn't work, fall back to physical
if (!zap || chdir(zap)) {
free(zap);
if (chdir(dd)) return perror_msg("%s", dd);
if (!(dd = getcwd(0, 0))) dd = xstrdup("(nowhere)");
} else dd = zap;
if ((pwd = getvar("PWD"))) setvarval("OLDPWD", pwd);
setvarval("PWD", dd);
free(dd);
if (!(TT.options&OPT_cd)) {
export("OLDPWD");
export("PWD");
TT.options |= OPT_cd;
}
}
void exit_main(void)
{
exit(*toys.optargs ? atoi(*toys.optargs) : 0);
}
// lib/args.c can't +prefix & "+o history" needs space so parse cmdline here
void set_main(void)
{
char *cc, *ostr[] = {"braceexpand", "noclobber", "xtrace"};
int ii, jj, kk, oo = 0, dd = 0;
// display visible variables
if (!*toys.optargs) {
struct sh_vars **vv = visible_vars();
// TODO escape properly
for (ii = 0; vv[ii]; ii++)
if (!(vv[ii]->flags&VAR_WHITEOUT)) printf("%s\n", vv[ii]->str);
free(vv);
return;
}
// Handle options
for (ii = 0;; ii++) {
if ((cc = toys.optargs[ii]) && !(dd = stridx("-+", *cc)+1) && oo--) {
for (jj = 0; jj<ARRAY_LEN(ostr); jj++) if (!strcmp(cc, ostr[jj])) break;
if (jj != ARRAY_LEN(ostr)) {
if (dd==1) TT.options |= OPT_B<<kk;
else TT.options &= ~(OPT_B<<kk);
continue;
}
error_exit("bad -o %s", cc);
}
if (oo>0) for (jj = 0; jj<ARRAY_LEN(ostr); jj++)
printf("%s\t%s\n", ostr[jj], TT.options&(OPT_B<<jj) ? "on" : "off");
oo = 0;
if (!cc || !dd) break;
for (jj = 1; cc[jj]; jj++) {
if (cc[jj] == 'o') oo++;
else if (-1 != (kk = stridx("BCx", cc[jj]))) {
if (*cc == '-') TT.options |= OPT_B<<kk;
else TT.options &= ~(OPT_B<<kk);
} else error_exit("bad -%c", toys.optargs[ii][1]);
}
}
// handle positional parameters
if (cc) {
struct arg_list *al, **head;
struct sh_arg *arg = &TT.ff->arg;
// don't free memory that's already scheduled for deletion
for (al = *(head = &TT.ff->delete); al; al = *(head = &al->next))
if (al->arg == (void *)arg->v) break;
// free last set's memory (if any) so it doesn't accumulate in loop
if (al) for (jj = arg->c+1; jj; jj--) {
*head = al->next;
free(al->arg);
free(al);
}
while (toys.optargs[ii])
arg_add(arg, push_arg(&TT.ff->delete, strdup(toys.optargs[ii++])));
push_arg(&TT.ff->delete, arg->v);
}
}
// TODO need test: unset clears var first and stops, function only if no var.
#define FOR_unset
#include "generated/flags.h"
void unset_main(void)
{
char **arg, *s;
int ii;
for (arg = toys.optargs; *arg; arg++) {
s = varend(*arg);
if (s == *arg || *s) {
error_msg("bad '%s'", *arg);
continue;
}
// TODO -n and name reference support
// unset variable
if (!FLAG(f) && unsetvar(*arg)) continue;
// unset function TODO binary search
for (ii = 0; ii<TT.funcslen; ii++)
if (!strcmp(*arg, TT.functions[ii]->name)) break;
if (ii != TT.funcslen) {
free_function(TT.functions[ii]);
memmove(TT.functions+ii, TT.functions+ii+1, TT.funcslen+1-ii);
}
}
}
#define FOR_export
#include "generated/flags.h"
void export_main(void)
{
char **arg, *eq;
// list existing variables?
if (!toys.optc) {
struct sh_vars **vv = visible_vars();
unsigned uu;
for (uu = 0; vv[uu]; uu++) {
if ((vv[uu]->flags&(VAR_WHITEOUT|VAR_EXPORT))==VAR_EXPORT) {
xputs(eq = declarep(vv[uu]));
free(eq);
}
}
free(vv);
return;
}
// set/move variables
for (arg = toys.optargs; *arg; arg++) {
eq = varend(*arg);
if (eq == *arg || (*eq && eq[*eq=='+'] != '=')) {
error_msg("bad %s", *arg);
continue;
}
if (FLAG(n)) set_varflags(*arg, 0, VAR_EXPORT);
else export(*arg);
}
}
#define FOR_declare
#include "generated/flags.h"
void declare_main(void)
{
unsigned uu, fl = toys.optflags&(FLAG(p)-1);
char *ss, **arg;
// TODO: need a show_vars() to collate all the visible_vars() loop output
// TODO: -g support including -gp
// TODO: dump everything key=value and functions too
if (!toys.optc) {
struct sh_vars **vv = visible_vars();
for (uu = 0; vv[uu]; uu++) {
if ((vv[uu]->flags&VAR_WHITEOUT) || (fl && !(vv[uu]->flags&fl))) continue;
xputs(ss = declarep(vv[uu]));
free(ss);
}
free(vv);
} else if (FLAG(p)) for (arg = toys.optargs; *arg; arg++) {
struct sh_vars *vv = *varend(ss = *arg) ? 0 : findvar(ss, 0);
if (!vv) perror_msg("%s: not found", ss);
else {
xputs(ss = declarep(vv));
free(ss);
}
} else for (arg = toys.optargs; *arg; arg++) {
ss = varend(*arg);
if (ss == *arg || (*ss && ss[*ss=='+'] != '=')) {
error_msg("bad %s", *arg);
continue;
}
set_varflags(*arg, toys.optflags<<1, 0); // TODO +x unset
}
}
void eval_main(void)
{
char *s;
// borrow the $* expand infrastructure
call_function();
TT.ff->arg.v = toys.argv;
TT.ff->arg.c = toys.optc+1;
s = expand_one_arg("\"$*\"", SEMI_IFS, 0);
TT.ff->arg.v = TT.ff->next->arg.v;
TT.ff->arg.c = TT.ff->next->arg.c;
do_source(0, fmemopen(s, strlen(s), "r"));
free(dlist_pop(&TT.ff));
free(s);
}
#define FOR_exec
#include "generated/flags.h"
void exec_main(void)
{
char *ee[1] = {0}, **old = environ;
// discard redirects and return if nothing to exec
free(TT.pp->urd);
TT.pp->urd = 0;
if (!toys.optc) return;
// exec, handling -acl
TT.isexec = *toys.optargs;
if (FLAG(c)) environ = ee;
if (TT.exec.a || FLAG(l))
*toys.optargs = xmprintf("%s%s", FLAG(l) ? "-" : "", TT.exec.a?:TT.isexec);
sh_exec(toys.optargs);
// report error (usually ENOENT) and return
perror_msg("%s", TT.isexec);
if (*toys.optargs != TT.isexec) free(*toys.optargs);
TT.isexec = 0;
toys.exitval = 127;
environ = old;
}
// Return T.jobs index or -1 from identifier
// Note, we don't return "ambiguous job spec", we return the first hit or -1.
// TODO %% %+ %- %?ab
int find_job(char *s)
{
char *ss;
long ll = strtol(s, &ss, 10);
int i, j;
if (!TT.jobs.c) return -1;
if (!*s || (!s[1] && strchr("%+-", *s))) {
int minus, plus = find_plus_minus(&minus);
return (*s == '-') ? minus : plus;
}
// Is this a %1 numeric jobspec?
if (s != ss && !*ss)
for (i = 0; i<TT.jobs.c; i++)
if (((struct sh_process *)TT.jobs.v[i])->job == ll) return i;
// Match start of command or %?abc
for (i = 0; i<TT.jobs.c; i++) {
struct sh_process *pp = (void *)TT.jobs.v[i];
if (strstart(&s, *pp->arg.v)) return i;
if (*s != '?' || !s[1]) continue;
for (j = 0; j<pp->arg.c; j++) if (strstr(pp->arg.v[j], s+1)) return i;
}
return -1;
}
void jobs_main(void)
{
int i, j, minus, plus = find_plus_minus(&minus);
char *s;
// TODO -lnprs
for (i = 0;;i++) {
if (toys.optc) {
if (!(s = toys.optargs[i])) break;
if ((j = find_job(s+('%' == *s))) == -1) {
perror_msg("%s: no such job", s);
continue;
}
} else if ((j = i) >= TT.jobs.c) break;
s = show_job((void *)TT.jobs.v[i], is_plus_minus(i, plus, minus));
printf("%s\n", s);
free(s);
}
}
#define FOR_local
#include "generated/flags.h"
void local_main(void)
{
struct sh_fcall *ff, *ff2;
struct sh_vars *var;
char **arg, *eq;
// find local variable context
for (ff = TT.ff;; ff = ff->next) {
if (ff == TT.ff->prev) return error_msg("not in function");
if (ff->vars) break;
}
// list existing vars (todo:
if (!toys.optc) {
for (var = ff->vars; var; var++) xputs(var->str); // TODO escape
return;
}
// set/move variables
for (arg = toys.optargs; *arg; arg++) {
if ((eq = varend(*arg)) == *arg || (*eq && *eq != '=')) {
error_msg("bad %s", *arg);
continue;
}
if ((var = findvar(*arg, &ff2)) && ff == ff2 && !*eq) continue;
if (var && (var->flags&VAR_READONLY)) {
error_msg("%.*s: readonly variable", (int)(varend(*arg)-*arg), *arg);
continue;
}
// Add local inheriting global status and setting whiteout if blank.
if (!var || ff!=ff2) {
int flags = var ? var->flags&VAR_EXPORT : 0;
var = addvar(xmprintf("%s%s", *arg, *eq ? "" : "="), ff);
var->flags = flags|(VAR_WHITEOUT*!*eq);
}
// TODO accept declare options to set more flags
// TODO, integer, uppercase take effect. Setvar?
}
}
void shift_main(void)
{
long long by = 1;
if (toys.optc) by = atolx(*toys.optargs);
by += TT.ff->shift;
if (by<0 || by>=TT.ff->arg.c) toys.exitval++;
else TT.ff->shift = by;
}
void source_main(void)
{
char *name = *toys.optargs;
FILE *ff = fpathopen(name);
if (!ff) return perror_msg_raw(name);
// $0 is shell name, not source file name while running this
// TODO add tests: sh -c "source input four five" one two three
*toys.optargs = *toys.argv;
++TT.srclvl;
call_function();
TT.ff->arg.v = toys.optargs;
TT.ff->arg.c = toys.optc;
TT.ff->oldlineno = TT.LINENO;
TT.LINENO = 0;
do_source(name, ff);
TT.LINENO = TT.ff->oldlineno;
free(dlist_pop(&TT.ff));
--TT.srclvl;
}
#define FOR_wait
#include "generated/flags.h"
void wait_main(void)
{
struct sh_process *pp;
int ii, jj;
long long ll;
char *s;
// TODO does -o pipefail affect return code here
if (FLAG(n)) toys.exitval = free_process(wait_job(-1, 0));
else if (!toys.optc) while (TT.jobs.c) {
if (!(pp = wait_job(-1, 0))) break;
} else for (ii = 0; ii<toys.optc; ii++) {
ll = estrtol(toys.optargs[ii], &s, 10);
if (errno || *s) {
if (-1 == (jj = find_job(toys.optargs[ii]))) {
error_msg("%s: bad pid/job", toys.optargs[ii]);
continue;
}
ll = ((struct sh_process *)TT.jobs.v[jj])->pid;
}
if (!(pp = wait_job(ll, 0))) {
if (toys.signal) toys.exitval = 128+toys.signal;
break;
}
toys.exitval = free_process(pp);
}
}