blob: 341ed67252ded7d31fc49469d86d358aaf27abff [file] [log] [blame]
/* util.h
* Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
* Logging and other utility functions.
#ifndef _UTIL_H_
#define _UTIL_H_
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <syslog.h>
#include <unistd.h>
#ifdef __cplusplus
extern "C" {
* Silence compiler warnings for unused variables/functions.
* If the definition is actually used, the attribute should be removed, but if
* it's forgotten or left in place, it doesn't cause a problem.
* If the definition is actually unused, the compiler is free to remove it from
* the output so as to save size. If you want to make sure the definition is
* kept (e.g. for ABI compatibility), look at the "used" attribute instead.
#define attribute_unused __attribute__((__unused__))
* Mark the symbol as "weak" in the ELF output. This provides a fallback symbol
* that may be overriden at link time. See this page for more details:
#define attribute_weak __attribute__((__weak__))
* Mark the function as a printf-style function.
* @format_idx The index in the function argument list where the format string
* is passed (where the first argument is "1").
* @check_idx The index in the function argument list where the first argument
* used in the format string is passed.
* Some examples:
* foo([1] const char *format, [2] ...): format=1 check=2
* foo([1] int, [2] const char *format, [3] ...): format=2 check=3
* foo([1] const char *format, [2] const char *, [3] ...): format=1 check=3
#define attribute_printf(format_idx, check_idx) \
__attribute__((__format__(__printf__, format_idx, check_idx)))
/* clang-format off */
#define die(_msg, ...) \
do_fatal_log(LOG_ERR, "libminijail[%d]: " _msg, getpid(), ## __VA_ARGS__)
#define pdie(_msg, ...) \
die(_msg ": %m", ## __VA_ARGS__)
#define warn(_msg, ...) \
do_log(LOG_WARNING, "libminijail[%d]: " _msg, getpid(), ## __VA_ARGS__)
#define pwarn(_msg, ...) \
warn(_msg ": %m", ## __VA_ARGS__)
#define info(_msg, ...) \
do_log(LOG_INFO, "libminijail[%d]: " _msg, getpid(), ## __VA_ARGS__)
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
/* clang-format on */
extern const char *log_syscalls[];
extern const size_t log_syscalls_len;
enum logging_system_t {
/* Log to syslog. This is the default. */
/* Log to a file descriptor. */
* Even though this function internally calls abort(2)/exit(2), it is
* intentionally not marked with the noreturn attribute. When marked as
* noreturn, clang coalesces several of the do_fatal_log() calls in methods that
* have a large number of such calls (like minijail_enter()), making it
* impossible for breakpad to correctly identify the line where it was called,
* making the backtrace somewhat useless.
extern void do_fatal_log(int priority, const char *format, ...)
attribute_printf(2, 3);
extern void do_log(int priority, const char *format, ...)
attribute_printf(2, 3);
static inline int is_android(void)
#if defined(__ANDROID__)
return 1;
return 0;
static inline bool running_with_asan(void)
#if defined(__SANITIZE_ADDRESS__)
/* For gcc. */
return true;
#elif defined(__has_feature)
/* For clang. */
return __has_feature(address_sanitizer);
return false;
int lookup_syscall(const char *name);
const char *lookup_syscall_name(int nr);
long int parse_single_constant(char *constant_str, char **endptr);
long int parse_constant(char *constant_str, char **endptr);
int parse_size(size_t *size, const char *sizespec);
char *strip(char *s);
* tokenize: locate the next token in @stringp using the @delim
* @stringp A pointer to the string to scan for tokens
* @delim The delimiter to split by
* Note that, unlike strtok, @delim is not a set of characters, but the full
* delimiter. e.g. "a,;b,;c" with a delim of ",;" will yield ["a","b","c"].
* Note that, unlike strtok, this may return an empty token. e.g. "a,,b" with
* strtok will yield ["a","b"], but this will yield ["a","","b"].
char *tokenize(char **stringp, const char *delim);
char *path_join(const char *external_path, const char *internal_path);
* consumebytes: consumes @length bytes from a buffer @buf of length @buflength
* @length Number of bytes to consume
* @buf Buffer to consume from
* @buflength Size of @buf
* Returns a pointer to the base of the bytes, or NULL for errors.
void *consumebytes(size_t length, char **buf, size_t *buflength);
* consumestr: consumes a C string from a buffer @buf of length @length
* @buf Buffer to consume
* @length Length of buffer
* Returns a pointer to the base of the string, or NULL for errors.
char *consumestr(char **buf, size_t *buflength);
* init_logging: initializes the module-wide logging.
* @logger The logging system to use.
* @fd The file descriptor to log into. Ignored unless
* @logger = LOG_TO_FD.
* @min_priority The minimum priority to display. Corresponds to syslog's
priority parameter. Ignored unless @logger = LOG_TO_FD.
void init_logging(enum logging_system_t logger, int fd, int min_priority);
#ifdef __cplusplus
}; /* extern "C" */
#endif /* _UTIL_H_ */