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-rw-r--r--libbb/strrstr.c75
1 files changed, 69 insertions, 6 deletions
diff --git a/libbb/strrstr.c b/libbb/strrstr.c
index b314264..3cd7667 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 <string.h>
+#include <stdio.h>
-/* 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