cosmopolitan/libc/calls/execvpe.c
Justine Tunney f531acc8f9
Make improvements
- Invent openatemp() API
- Invent O_UNLINK open flag
- Introduce getenv_secure() API
- Remove `git pull` from cosmocc
- Fix utimes() when path is NULL
- Fix mktemp() to never return NULL
- Fix utimensat() UTIME_OMIT on XNU
- Improve utimensat() code for RHEL5
- Turn `argv[0]` C:/ to /C/ on Windows
- Introduce tmpnam() and tmpnam_r() APIs
- Fix more const issues with internal APIs
- Permit utimes() on WIN32 in O_RDONLY mode
- Fix fdopendir() to check fd is a directory
- Fix recent crash regression in landlock make
- Fix futimens(AT_FDCWD, NULL) to return EBADF
- Use workaround so `make -j` doesn't fork bomb
- Rename dontdiscard to __wur (just like glibc)
- Fix st_size for WIN32 symlinks containing UTF-8
- Introduce stdio ext APIs needed by GNU coreutils
- Fix lstat() on WIN32 for symlinks to directories
- Move some constants from normalize.inc to limits.h
- Fix segv with memchr() and memcmp() overlapping page
- Implement POSIX fflush() behavior for reader streams
- Implement AT_SYMLINK_NOFOLLOW for utimensat() on WIN32
- Don't change read-only status of existing files on WIN32
- Correctly handle `0x[^[:xdigit:]]` case in strtol() functions
2023-09-06 12:34:59 -07:00

75 lines
3.4 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/dce.h"
#include "libc/intrin/asan.internal.h"
#include "libc/limits.h"
#include "libc/mem/alloca.h"
#include "libc/mem/mem.h"
#include "libc/str/str.h"
#include "libc/sysv/errfuns.h"
/**
* Executes program, with path environment search.
*
* This function is a wrapper of the execve() system call that does path
* resolution. The `PATH` environment variable is taken from your global
* `environ` rather than the `envp` argument.
*
* @param prog is the program to launch
* @param argv is [file,argv₁..argvₙ₋₁,NULL]
* @param envp is ["key=val",...,NULL]
* @return doesn't return on success, otherwise -1 w/ errno
* @asyncsignalsafe
* @vforksafe
*/
int execvpe(const char *prog, char *const argv[], char *const *envp) {
size_t i;
char *exe, **argv2;
char pathbuf[PATH_MAX];
// validate memory
if (IsAsan() &&
(!__asan_is_valid_str(prog) || !__asan_is_valid_strlist(argv))) {
return efault();
}
if (strchr(prog, '/')) {
return execve(prog, argv, envp);
}
// resolve path of executable
if (!(exe = commandv(prog, pathbuf, sizeof(pathbuf)))) {
return -1;
}
// change argv[0] to resolved path if it's ambiguous
// otherwise the program won't have much luck finding itself
if (argv[0] && *prog != '/' && *exe == '/' && !strcmp(prog, argv[0])) {
for (i = 0; argv[i++];) (void)0;
argv2 = alloca(i * sizeof(*argv));
memcpy(argv2, argv, i * sizeof(*argv));
argv2[0] = exe;
argv = argv2;
}
// execute program
// tail call shouldn't be possible
return execve(exe, argv, envp);
}