Initial revision

strrepl.c

@@ -0,0 +1,75 @@
+/*
+   --------------------------------------------------------------------
+   Module:     REPLACE.C
+   Author:     Gilles Kohl
+   Started:    09.06.1992   12:16:47
+   Modified:   09.06.1992   12:41:41
+   Subject:    Replace one string by another in a given buffer.
+               This code is public domain. Use freely.
+   --------------------------------------------------------------------
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+/*
+ * StrReplace: Replace OldStr by NewStr in string Str.
+ *
+ * Str should have enough allocated space for the replacement, no check
+ * is made for this. Str and OldStr/NewStr should not overlap.
+ * The empty string ("") is found at the beginning of every string.
+ *
+ * Returns: pointer to first location behind where NewStr was inserted
+ * or NULL if OldStr was not found.
+ * This is useful for multiple replacements, see example in main() below
+ * (be careful not to replace the empty string this way !)
+ */
+
+char *StrReplace(char *Str, char *OldStr, char *NewStr)
+{
+      int OldLen, NewLen;
+      char *p, *q;
+
+      if(NULL == (p = strstr(Str, OldStr)))
+            return p;
+      OldLen = strlen(OldStr);
+      NewLen = strlen(NewStr);
+      memmove(q = p+NewLen, p+OldLen, strlen(p+OldLen)+1);
+      memcpy(p, NewStr, NewLen);
+      return q;
+}
+
+#ifdef TEST
+
+/*
+ * Test main().
+ * Given two arguments, replaces the first arg. in the lines read from
+ * stdin by the second one.
+ * Example invocation:
+ * replace printf puts <replace.c
+ * will replace all printf's by puts in replace's source.
+ *
+ */
+
+int main(int argc, char *argv[])
+{
+      char buf[200];
+      char *Start;
+
+      if(argc != 3)
+            exit(1);
+
+      /* Repeat until all occurences replaced */
+
+      while(NULL != (Start = gets(buf)))
+      {
+            while(NULL != (Start = StrReplace(Start, argv[1], argv[2])))
+                  ;
+            printf("%s\n", buf);
+      }
+      return 0;
+}
+
+#endif 
+