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authoryctct <yctct@yctct.com>2026-02-05 11:56:49 +0100
committeryctct <yctct@yctct.com>2026-02-05 11:56:49 +0100
commit861a36d86e7587c043131228cf3a08afd7bc43ad (patch)
treea931df9f1845250c0e93adeda52f139c2f5ee1b0 /ft_strnstr.c
Add files, first commit
Diffstat (limited to 'ft_strnstr.c')
-rw-r--r--ft_strnstr.c113
1 files changed, 113 insertions, 0 deletions
diff --git a/ft_strnstr.c b/ft_strnstr.c
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index 0000000..f7042d6
--- /dev/null
+++ b/ft_strnstr.c
@@ -0,0 +1,113 @@
+/*
+Libft Copyright (C) 2026 yctct
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include "libft.h"
+
+char *ft_strnstr(const char *big, const char *little, size_t len)
+{
+ unsigned long i;
+ int j;
+
+ if (ft_strlen(little) <= 0)
+ return ((char *)(big));
+ i = 0;
+ while (big[i] != '\0' && i < len)
+ {
+ if (big[i] == little[0])
+ {
+ j = 0;
+ while (big[i + j] == little[j] && little[j] && (i + j) < len)
+ j++;
+ if (little[j] == '\0')
+ return ((char *)(&big[i]));
+ }
+ i++;
+ }
+ return (NULL);
+}
+/*
+#include <bsd/string.h>
+#include <stdio.h>
+#include <string.h>
+
+int main(void)
+{
+ const char *largestring = "Foo Bar Caz";
+ const char *smallstring = "Bar";
+ const char *empty_smallstring = "";
+ const char *largestring2 = "Foo Baz Caz";
+ const char *smallstring2 = "Bar";
+ const char *largestring3 = "Foo Bar Baz";
+ const char *smallstring3 = "Baz";
+
+ printf(" the big string is: %s\n", largestring);
+ printf("the small string is: %s\n", smallstring);
+ printf(" strnstr: %s\n",
+strnstr(largestring, smallstring, 7));
+ printf(" ft_strnstr: %s\n",
+ft_strnstr(largestring, smallstring, 7));
+ printf("----------------------------------
+---------------------------------\n");
+ printf("When the small string is empty,
+ the function returns the big string\n");
+ printf(" the big string is: %s\n", largestring);
+ printf("the small string is: %s\n", empty_smallstring);
+ printf(" strnstr: %s\n",
+strnstr(largestring, empty_smallstring, 7));
+ printf(" ft_strnstr: %s\n",
+ft_strnstr(largestring, empty_smallstring, 7));
+ printf("------------------------------
+-------------------------------------\n");
+ printf("When the little string occurs
+nowhere in big, NULL is returned\n");
+ printf(" the big string is: %s\n", largestring2);
+ printf("the small string is: %s\n", smallstring2);
+ printf(" strnstr: %s\n",
+strnstr(largestring2, smallstring2, 7));
+ printf(" ft_strnstr: %s\n",
+ft_strnstr(largestring2, smallstring2, 7));
+ printf("-------------------------------
+------------------------------------\n");
+ printf("When the little string occurs
+at the end of big\n");
+ printf(" the big string is: %s\n", largestring3);
+ printf("the small string is: %s\n", smallstring3);
+ printf(" strnstr: %s\n",
+strnstr(largestring3, smallstring3, 11));
+ printf(" ft_strnstr: %s\n",
+ft_strnstr(largestring3, smallstring3, 11));
+ printf("-----------------------------------
+--------------------------------\n");
+ printf("When length is smaller than
+necessary to print little\n");
+ printf(" the big string is: %s\n", largestring3);
+ printf("the small string is: %s\n", smallstring3);
+ printf(" strnstr: %s\n",
+strnstr(largestring3, smallstring3, 10));
+ printf(" ft_strnstr: %s\n",
+ft_strnstr(largestring3, smallstring3, 10));
+ printf("----------------------------
+---------------------------------------\n");
+ printf("When length is zero\n");
+ printf(" the big string is: %s\n", largestring3);
+ printf("the small string is: %s\n", smallstring3);
+ printf(" strnstr: %s\n",
+strnstr(largestring3, smallstring3, 0));
+ printf(" ft_strnstr: %s\n",
+ft_strnstr(largestring3, smallstring3, 0));
+}
+*/