| /* vi: set sw=4 ts=4: */ |
| /* |
| * Utility routines. |
| * |
| * Copyright (C) 2006 Gabriel Somlo <somlo at cmu.edu> |
| * |
| * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| */ |
| |
| #include "libbb.h" |
| |
| /* check if path points to an executable file; |
| * return 1 if found; |
| * return 0 otherwise; |
| */ |
| int FAST_FUNC execable_file(const char *name) |
| { |
| struct stat s; |
| return (!access(name, X_OK) && !stat(name, &s) && S_ISREG(s.st_mode)); |
| } |
| |
| /* search (*PATHp) for an executable file; |
| * return allocated string containing full path if found; |
| * PATHp points to the component after the one where it was found |
| * (or NULL), |
| * you may call find_execable again with this PATHp to continue |
| * (if it's not NULL). |
| * return NULL otherwise; (PATHp is undefined) |
| * in all cases (*PATHp) contents will be trashed (s/:/NUL/). |
| */ |
| char* FAST_FUNC find_execable(const char *filename, char **PATHp) |
| { |
| char *p, *n; |
| |
| p = *PATHp; |
| while (p) { |
| n = strchr(p, ':'); |
| if (n) |
| *n++ = '\0'; |
| if (*p != '\0') { /* it's not a PATH="foo::bar" situation */ |
| p = concat_path_file(p, filename); |
| if (execable_file(p)) { |
| *PATHp = n; |
| return p; |
| } |
| free(p); |
| } |
| p = n; |
| } /* on loop exit p == NULL */ |
| return p; |
| } |
| |
| /* search $PATH for an executable file; |
| * return 1 if found; |
| * return 0 otherwise; |
| */ |
| int FAST_FUNC exists_execable(const char *filename) |
| { |
| char *path = xstrdup(getenv("PATH")); |
| char *tmp = path; |
| char *ret = find_execable(filename, &tmp); |
| free(path); |
| if (ret) { |
| free(ret); |
| return 1; |
| } |
| return 0; |
| } |
| |
| #if ENABLE_FEATURE_PREFER_APPLETS |
| /* just like the real execvp, but try to launch an applet named 'file' first */ |
| int FAST_FUNC BB_EXECVP(const char *file, char *const argv[]) |
| { |
| if (find_applet_by_name(file) >= 0) |
| execvp(bb_busybox_exec_path, argv); |
| return execvp(file, argv); |
| } |
| #endif |
| |
| int FAST_FUNC BB_EXECVP_or_die(char **argv) |
| { |
| BB_EXECVP(argv[0], argv); |
| /* SUSv3-mandated exit codes */ |
| xfunc_error_retval = (errno == ENOENT) ? 127 : 126; |
| bb_perror_msg_and_die("can't execute '%s'", argv[0]); |
| } |