From e765b5ac349a8f9305e52b3ab2c3ac78c17bf283 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Fri, 2 May 2014 17:15:58 +0200 Subject: libbb: rename execable -> executable. No code changes English speakers complained that it sounded awfully broken. Signed-off-by: Denys Vlasenko --- libbb/executable.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) create mode 100644 libbb/executable.c (limited to 'libbb/executable.c') diff --git a/libbb/executable.c b/libbb/executable.c new file mode 100644 index 000000000..85ecc3e6c --- /dev/null +++ b/libbb/executable.c @@ -0,0 +1,92 @@ +/* vi: set sw=4 ts=4: */ +/* + * Utility routines. + * + * Copyright (C) 2006 Gabriel Somlo + * + * 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 file_is_executable(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_executable 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_executable(const char *filename, char **PATHp) +{ + /* About empty components in $PATH: + * http://pubs.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap08.html + * 8.3 Other Environment Variables - PATH + * A zero-length prefix is a legacy feature that indicates the current + * working directory. It appears as two adjacent colons ( "::" ), as an + * initial colon preceding the rest of the list, or as a trailing colon + * following the rest of the list. + */ + char *p, *n; + + p = *PATHp; + while (p) { + n = strchr(p, ':'); + if (n) + *n++ = '\0'; + p = concat_path_file( + p[0] ? p : ".", /* handle "::" case */ + filename + ); + if (file_is_executable(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 executable_exists(const char *filename) +{ + char *path = xstrdup(getenv("PATH")); + char *tmp = path; + char *ret = find_executable(filename, &tmp); + free(path); + free(ret); + return ret != NULL; +} + +#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]); +} -- cgit v1.2.3