emo/busybox
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

strrchr: bikeshed painting time!

Browse Source 
replace cubic running time implementation with quadratic
 make embedded test actually readable

function                                             old     new   delta
strrstr                                               42      44      +2
This commit is contained in:
Denis Vlasenko 2008-06-18 19:49:46 +00:00
parent 9cd4c76b50
commit d5736c5607
1 changed files with 43 additions and 51 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

92
libbb/strrstr.c
View File

@ -7,73 +7,65 @@
* Licensed under GPLv2 or later, see file License in this tarball for details. * Licensed under GPLv2 or later, see file License in this tarball for details.
*/ */
#ifdef __DO_STRRSTR_TEST
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#else
#include "libbb.h" #include "libbb.h"
#endif
/* /*
* The strrstr() function finds the last occurrence of the substring needle * The strrstr() function finds the last occurrence of the substring needle
* in the string haystack. The terminating nul characters are not compared. * in the string haystack. The terminating nul characters are not compared.
*/ */
char *strrstr(const char *haystack, const char *needle) char* strrstr(const char *haystack, const char *needle)
{ {
char *r = NULL; char *r = NULL;
do { if (!needle[0])
return (char*)haystack;
while (1) {
char *p = strstr(haystack, needle); char *p = strstr(haystack, needle);
if (p) if (!p)
r = p; return r;
} while (*haystack++); r = p;
return r; haystack = p + 1;
}
} }
#ifdef __DO_STRRSTR_TEST #ifdef __DO_STRRSTR_TEST
/* Test */
int main(int argc, char **argv) int main(int argc, char **argv)
{ {
int ret = 0; static const struct {
int n; const char *h, *n;
char *tmp; int pos;
} test_array[] = {
/* 0123456789 */
{ "baaabaaab", "aaa", 5 },
{ "baaabaaaab", "aaa", 6 },
{ "baaabaab", "aaa", 1 },
{ "aaa", "aaa", 0 },
{ "aaa", "a", 2 },
{ "aaa", "bbb", -1 },
{ "a", "aaa", -1 },
{ "aaa", "", 3 },
{ "", "aaa", -1 },
{ "", "", 0 },
};
ret |= !(n = ((tmp = strrstr("baaabaaab", "aaa")) != NULL && strcmp(tmp, "aaab") == 0)); int i;
printf("'baaabaaab' vs. 'aaa' : %s\n", n ? "PASSED" : "FAILED");
ret |= !(n = ((tmp = strrstr("baaabaaaab", "aaa")) != NULL && strcmp(tmp, "aaab") == 0)); i = 0;
printf("'baaabaaaab' vs. 'aaa' : %s\n", n ? "PASSED" : "FAILED"); while (i < sizeof(test_array) / sizeof(test_array[0])) {
const char *r = strrstr(test_array[i].h, test_array[i].n);
printf("'%s' vs. '%s': '%s' - ", test_array[i].h, test_array[i].n, r);
if (r == NULL)
r = test_array[i].h - 1;
printf("%s\n", r == test_array[i].h + test_array[i].pos ? "PASSED" : "FAILED");
i++;
}
ret |= !(n = ((tmp = strrstr("baaabaab", "aaa")) != NULL && strcmp(tmp, "aaabaab") == 0)); return 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 #endif