blob: 4fec41b73f3bbe4ad2a011c9f91470159b321d59 [file] [log] [blame]
/* getmountlist.c - Get a linked list of mount points, with stat information.
*
* Copyright 2006 Rob Landley <rob@landley.net>
*/
#include "toys.h"
#include <mntent.h>
// Realloc *old with oldstring,newstring
void comma_collate(char **old, char *new)
{
char *temp, *atold = *old;
// Only add a comma if old string didn't end with one
if (atold && *atold) {
char *comma = ",";
if (atold[strlen(atold)-1] == ',') comma = "";
temp = xmprintf("%s%s%s", atold, comma, new);
} else temp = xstrdup(new);
free (atold);
*old = temp;
}
// iterate through strings in a comma separated list.
// returns start of next entry or NULL if none
// sets *len to length of entry (not including comma)
// advances *list to start of next entry
char *comma_iterate(char **list, int *len)
{
char *start = *list, *end;
if (!*list || !**list) return 0;
if (!(end = strchr(*list, ','))) {
*len = strlen(*list);
*list = 0;
} else *list += (*len = end-start)+1;
return start;
}
static void octal_deslash(char *s)
{
char *o = s;
while (*s) {
if (*s == '\\') {
int i, oct = 0;
for (i = 1; i < 4; i++) {
if (!isdigit(s[i])) break;
oct = (oct<<3)+s[i]-'0';
}
if (i == 4) {
*o++ = oct;
s += i;
continue;
}
}
*o++ = *s++;
}
*o = 0;
}
// check all instances of opt and "no"opt in optlist, return true if opt
// found and last instance wasn't no. If clean, remove each instance from list.
int comma_scan(char *optlist, char *opt, int clean)
{
int optlen = strlen(opt), len, no, got = 0;
if (optlist) for (;;) {
char *s = comma_iterate(&optlist, &len);
if (!s) break;
no = 2*(*s == 'n' && s[1] == 'o');
if (optlen == len-no && !strncmp(opt, s+no, optlen)) {
got = !no;
if (clean && optlist) memmove(s, optlist, strlen(optlist)+1);
}
}
return got;
}
// return true if all scanlist options enabled in optlist
int comma_scanall(char *optlist, char *scanlist)
{
int i = 1;
while (scanlist && *scanlist) {
char *opt = comma_iterate(&scanlist, &i), *s = xstrndup(opt, i);
i = comma_scan(optlist, s, 0);
free(s);
if (!i) break;
}
return i;
}
// Check if this type matches list.
// Odd syntax: typelist all yes = if any, typelist all no = if none.
int mountlist_istype(struct mtab_list *ml, char *typelist)
{
int len, skip;
char *t;
if (!typelist) return 1;
skip = strncmp(typelist, "no", 2);
for (;;) {
if (!(t = comma_iterate(&typelist, &len))) break;
if (!skip) {
// If one -t starts with "no", the rest must too
if (strncmp(t, "no", 2)) error_exit("bad typelist");
if (!strncmp(t+2, ml->type, len-2)) {
skip = 1;
break;
}
} else if (!strncmp(t, ml->type, len) && !ml->type[len]) {
skip = 0;
break;
}
}
return !skip;
}
// Get list of mounted filesystems, including stat and statvfs info.
// Returns a reversed list, which is good for finding overmounts and such.
struct mtab_list *xgetmountlist(char *path)
{
struct mtab_list *mtlist = 0, *mt;
struct mntent *me;
FILE *fp;
char *p = path ? path : "/proc/mounts";
if (!(fp = setmntent(p, "r"))) perror_exit("bad %s", p);
// The "test" part of the loop is done before the first time through and
// again after each "increment", so putting the actual load there avoids
// duplicating it. If the load was NULL, the loop stops.
while ((me = getmntent(fp))) {
mt = xzalloc(sizeof(struct mtab_list) + strlen(me->mnt_fsname) +
strlen(me->mnt_dir) + strlen(me->mnt_type) + strlen(me->mnt_opts) + 4);
dlist_add_nomalloc((void *)&mtlist, (void *)mt);
// Collect details about mounted filesystem
// Don't report errors, just leave data zeroed
if (!path) {
stat(me->mnt_dir, &(mt->stat));
statvfs(me->mnt_dir, &(mt->statvfs));
}
// Remember information from /proc/mounts
mt->dir = stpcpy(mt->type, me->mnt_type)+1;
mt->device = stpcpy(mt->dir, me->mnt_dir)+1;
mt->opts = stpcpy(mt->device, me->mnt_fsname)+1;
strcpy(mt->opts, me->mnt_opts);
octal_deslash(mt->dir);
octal_deslash(mt->device);
}
endmntent(fp);
return mtlist;
}