& must be encoded as &

[prss.git] / src / pstr.c

diff --git a/src/pstr.c b/src/pstr.c
new file mode 100644 (file)
index 0000000..fb4f937
--- /dev/null
+++ b/src/pstr.c
@@ -0,0 +1,100 @@
+/*
+ Copyright (C) 2011-2014 jeanfi@gmail.com
+
+ 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 2 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, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ 02110-1301 USA
+ */
+
+#include <string.h>
+
+#include <pstr.h>
+
+char *strrep(char *str, const char *old, const char *new)
+{
+       char *p, *res;
+       int pos;
+
+       if (!str)
+               return NULL;
+
+       if (!*str || !old || !*old || !new || !strcmp(old, new))
+               return str;
+
+       p = strstr(str, old);
+
+       if (!p)
+               return str;
+
+       res = malloc(strlen(str) + (new ? strlen(new) : 0) - strlen(old) + 1);
+
+       pos = p - str;
+
+       strncpy(res, str, pos);
+       res[pos] = '\0';
+
+       if (new)
+               strcat(res + pos, new);
+
+       strcat(res, str + pos + strlen(old));
+
+       return res;
+}
+
+/*
+  Derivated from http://stackoverflow.com/questions/779875/what-is-the-function-to-replace-string-in-c
+*/
+char *strrepg(char *orig, const char *rep, const char *with) {
+    char *result; // the return string
+    char *ins;    // the next insert point
+    char *tmp;    // varies
+    int len_rep;  // length of rep
+    int len_with; // length of with
+    int len_front; // distance between rep and end of last rep
+    int count;    // number of replacements
+
+    if (!orig)
+        return NULL;
+    if (!rep)
+        rep = "";
+    len_rep = strlen(rep);
+    if (!with)
+        with = "";
+    len_with = strlen(with);
+
+    ins = orig;
+    for(count = 0; (tmp = strstr(ins, rep)); count++) {
+        ins = tmp + len_rep;
+    }
+
+    // first time through the loop, all the variable are set correctly
+    // from here on,
+    //    tmp points to the end of the result string
+    //    ins points to the next occurrence of rep in orig
+    //    orig points to the remainder of orig after "end of rep"
+    tmp = result = malloc(strlen(orig) + (len_with - len_rep) * count + 1);
+
+    if (!result)
+        return NULL;
+
+    while (count--) {
+        ins = strstr(orig, rep);
+        len_front = ins - orig;
+        tmp = strncpy(tmp, orig, len_front) + len_front;
+        tmp = strcpy(tmp, with) + len_with;
+        orig += len_front + len_rep; // move to next "end of rep"
+    }
+    strcpy(tmp, orig);
+    return result;
+}