From 15a357e5962634c94ee322fee4da897312090a89 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Fri, 2 May 2014 17:08:29 +0200 Subject: [PATCH] libbb: fix empty PATH components handling function old new delta find_execable 81 86 +5 exists_execable 71 66 -5 Signed-off-by: Denys Vlasenko --- libbb/execable.c | 30 ++++++++++++++++++------------ 1 file changed, 18 insertions(+), 12 deletions(-) diff --git a/libbb/execable.c b/libbb/execable.c index 178a00a5f..a3caea6f9 100644 --- a/libbb/execable.c +++ b/libbb/execable.c @@ -30,6 +30,14 @@ int FAST_FUNC execable_file(const char *name) */ char* FAST_FUNC find_execable(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; @@ -37,14 +45,15 @@ char* FAST_FUNC find_execable(const char *filename, char **PATHp) 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 = concat_path_file( + p[0] ? p : ".", /* handle "::" case */ + filename + ); + if (execable_file(p)) { + *PATHp = n; + return p; } + free(p); p = n; } /* on loop exit p == NULL */ return p; @@ -60,11 +69,8 @@ int FAST_FUNC exists_execable(const char *filename) char *tmp = path; char *ret = find_execable(filename, &tmp); free(path); - if (ret) { - free(ret); - return 1; - } - return 0; + free(ret); + return ret != NULL; } #if ENABLE_FEATURE_PREFER_APPLETS -- 2.25.1