From 13436ea0dd2b70271d30bd6f682cc9cbe41b26c6 Mon Sep 17 00:00:00 2001 From: Bernhard Reutner-Fischer Date: Tue, 17 Jun 2008 12:11:34 +0000 Subject: - improved strrstr impl from vda with testcases from Tito and vda --- libbb/strrstr.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 69 insertions(+), 6 deletions(-) (limited to 'libbb/strrstr.c') diff --git a/libbb/strrstr.c b/libbb/strrstr.c index b314264f5..3cd76670a 100644 --- a/libbb/strrstr.c +++ b/libbb/strrstr.c @@ -7,14 +7,77 @@ * Licensed under GPLv2 or later, see file License in this tarball for details. */ -#include "libbb.h" +#include +#include -/* reverse strstr() */ +/* + * The strrstr() function finds the last occurrence of the substring needle + * in the string haystack. The terminating nul characters are not compared. + */ char* strrstr(const char *haystack, const char *needle) { - char *tmp = strrchr(haystack, *needle); - if (tmp == NULL || strcmp(tmp, needle) != 0) - return NULL; - return tmp; + char *r = NULL; + + if (!needle[0]) + return r; + while (1) { + char *p = strstr(haystack, needle); + if (!p) + return r; + r = p; + haystack = p + 1; + } } +#ifdef __DO_STRRSTR_TEST +/* Test */ +int main(int argc, char **argv) +{ + int ret = 0; + int n; + char *tmp; + + ret |= !(n = ((tmp = strrstr("baaabaaab", "aaa")) != NULL && strcmp(tmp, "aaab") == 0)); + printf("'baaabaaab' vs. 'aaa' : %s\n", n ? "PASSED" : "FAILED"); + + ret |= !(n = ((tmp = strrstr("baaabaaaab", "aaa")) != NULL && strcmp(tmp, "aaab") == 0)); + printf("'baaabaaaab' vs. 'aaa' : %s\n", n ? "PASSED" : "FAILED"); + + ret |= !(n = ((tmp = strrstr("baaabaab", "aaa")) != NULL && strcmp(tmp, "aaabaab") == 0)); + printf("'baaabaab' vs. 'aaa' : %s\n", n ? "PASSED" : "FAILED"); + + ret |= !(n = (strrstr("aaa", "aaa") != NULL)); + printf("'aaa' vs. 'aaa' : %s\n", n ? "PASSED" : "FAILED"); + + ret |= !(n = (strrstr("aaa", "a") != NULL)); + printf("'aaa' vs. 'a' : %s\n", n ? "PASSED" : "FAILED"); + + ret |= !(n = (strrstr("aaa", "bbb") == NULL)); + printf("'aaa' vs. 'bbb' : %s\n", n ? "PASSED" : "FAILED"); + + ret |= !(n = (strrstr("a", "aaa") == NULL)); + printf("'a' vs. 'aaa' : %s\n", n ? "PASSED" : "FAILED"); + + ret |= !(n = ((tmp = strrstr("aaa", "")) != NULL && strcmp(tmp, "aaa") == 0)); + printf("'aaa' vs. '' : %s\n", n ? "FAILED" : "PASSED"); + + ret |= !(n = (strrstr("", "aaa") == NULL)); + printf("'' vs. 'aaa' : %s\n", n ? "PASSED" : "FAILED"); + + ret |= !(n = ((tmp = strrstr("", "")) != NULL && strcmp(tmp, "") == 0)); + printf("'' vs. '' : %s\n", n ? "PASSED" : "FAILED"); + + /*ret |= !(n = (strrstr(NULL, NULL) == NULL)); + printf("'NULL' vs. 'NULL' : %s\n", n ? "PASSED" : "FAILED"); + ret |= !(n = (strrstr("", NULL) == NULL)); + printf("'' vs. 'NULL' : %s\n", n ? "PASSED" : "FAILED"); + ret |= !(n = (strrstr(NULL, "") == NULL)); + printf("'NULL' vs. '' : %s\n", n ? "PASSED" : "FAILED"); + ret |= !(n = (strrstr("aaa", NULL) == NULL)); + printf("'aaa' vs. 'NULL' : %s\n", n ? "PASSED" : "FAILED"); + ret |= !(n = (strrstr(NULL, "aaa") == NULL)); + printf("'NULL' vs. 'aaa' : %s\n", n ? "PASSED" : "FAILED");*/ + + return ret; +} +#endif -- cgit v1.2.3