X-Git-Url: https://git.octo.it/?p=collectd.git;a=blobdiff_plain;f=src%2Fdaemon%2Futils_subst.c;h=a016342540cf95332074bcb395a6564adc512316;hp=3e554973c7698dc54bd6d32c0d612e11270a1223;hb=7111bb6df7628edce3a8e538b386fbe27633a191;hpb=e0e307657d6b751d6beb5afb92c9359a6df7f5e8

diff --git a/src/daemon/utils_subst.c b/src/daemon/utils_subst.c
index 3e554973..a0163425 100644
--- a/src/daemon/utils_subst.c
+++ b/src/daemon/utils_subst.c
@@ -29,122 +29,133 @@
  */
 
 #include "collectd.h"
+
 #include "common.h"
 #include "utils_subst.h"
 
-char *subst (char *buf, size_t buflen, const char *string, int off1, int off2,
-		const char *replacement)
-{
-	char  *buf_ptr = buf;
-	size_t len     = buflen;
-
-	if ((NULL == buf) || (0 >= buflen) || (NULL == string)
-			|| (0 > off1) || (0 > off2) || (off1 > off2)
-			|| (NULL == replacement))
-		return NULL;
-
-	sstrncpy (buf_ptr, string,
-			((size_t)off1 + 1 > buflen) ? buflen : (size_t)off1 + 1);
-	buf_ptr += off1;
-	len     -= off1;
-
-	if (0 >= len)
-		return buf;
-
-	sstrncpy (buf_ptr, replacement, len);
-	buf_ptr += strlen (replacement);
-	len     -= strlen (replacement);
-
-	if (0 >= len)
-		return buf;
-
-	sstrncpy (buf_ptr, string + off2, len);
-	return buf;
+char *subst(char *buf, size_t buflen, const char *string, size_t off1,
+            size_t off2, const char *replacement) {
+  char *out = buf;
+
+  char const *front;
+  char const *back;
+  size_t front_len;
+  size_t replacement_len;
+  size_t back_len;
+
+  if ((NULL == buf) || (0 == buflen) || (NULL == string) ||
+      (NULL == replacement))
+    return NULL;
+
+  size_t string_len = strlen(string);
+  if ((off1 > string_len) || (off2 > string_len) || (off1 > off2))
+    return NULL;
+
+  front = string;
+  back = string + off2;
+  front_len = off1;
+  replacement_len = strlen(replacement);
+  back_len = strlen(back);
+
+  if (front_len >= buflen) {
+    front_len = buflen - 1;
+    replacement_len = 0;
+    back_len = 0;
+  } else if ((front_len + replacement_len) >= buflen) {
+    replacement_len = buflen - (front_len + 1);
+    back_len = 0;
+  } else if ((front_len + replacement_len + back_len) >= buflen) {
+    back_len = buflen - (front_len + replacement_len + 1);
+  } else {
+    buflen = front_len + replacement_len + back_len + 1;
+  }
+  assert((front_len + replacement_len + back_len) == (buflen - 1));
+
+  if (front_len != 0) {
+    sstrncpy(out, front, front_len + 1);
+    out += front_len;
+  }
+
+  if (replacement_len != 0) {
+    sstrncpy(out, replacement, replacement_len + 1);
+    out += replacement_len;
+  }
+
+  if (back_len != 0) {
+    sstrncpy(out, back, back_len + 1);
+    out += back_len;
+  }
+
+  out[0] = 0;
+  return buf;
 } /* subst */
 
-char *asubst (const char *string, int off1, int off2, const char *replacement)
-{
-	char *buf;
-	int   len;
+char *asubst(const char *string, int off1, int off2, const char *replacement) {
+  char *buf;
+  int len;
 
-	char *ret;
+  char *ret;
 
-	if ((NULL == string) || (0 > off1) || (0 > off2) || (off1 > off2)
-			|| (NULL ==replacement))
-		return NULL;
+  if ((NULL == string) || (0 > off1) || (0 > off2) || (off1 > off2) ||
+      (NULL == replacement))
+    return NULL;
 
-	len = off1 + strlen (replacement) + strlen (string) - off2 + 1;
+  len = off1 + strlen(replacement) + strlen(string) - off2 + 1;
 
-	buf = (char *)malloc (len);
-	if (NULL == buf)
-		return NULL;
+  buf = malloc(len);
+  if (NULL == buf)
+    return NULL;
 
-	ret = subst (buf, len, string, off1, off2, replacement);
-	if (NULL == ret)
-		free (buf);
-	return ret;
+  ret = subst(buf, len, string, off1, off2, replacement);
+  if (NULL == ret)
+    free(buf);
+  return ret;
 } /* asubst */
 
-char *subst_string (char *buf, size_t buflen, const char *string,
-		const char *needle, const char *replacement)
-{
-	char *temp;
-	size_t needle_len;
-	size_t i;
-
-	if ((buf == NULL) || (string == NULL)
-			|| (needle == NULL) || (replacement == NULL))
-		return (NULL);
-
-	temp = (char *) malloc (buflen);
-	if (temp == NULL)
-	{
-		ERROR ("subst_string: malloc failed.");
-		return (NULL);
-	}
-
-	needle_len = strlen (needle);
-	strncpy (buf, string, buflen);
-
-	/* Limit the loop to prevent endless loops. */
-	for (i = 0; i < buflen; i++)
-	{
-		char *begin_ptr;
-		size_t begin;
-
-		/* Find `needle' in `buf'. */
-		begin_ptr = strstr (buf, needle);
-		if (begin_ptr == NULL)
-			break;
-
-		/* Calculate the start offset. */
-		begin = begin_ptr - buf;
-
-		/* Substitute the region using `subst'. The result is stored in
-		 * `temp'. */
-		begin_ptr = subst (temp, buflen, buf,
-				begin, begin + needle_len,
-				replacement);
-		if (begin_ptr == NULL)
-		{
-			WARNING ("subst_string: subst failed.");
-			break;
-		}
-
-		/* Copy the new string in `temp' to `buf' for the next round. */
-		strncpy (buf, temp, buflen);
-	}
-
-	if (i >= buflen)
-	{
-		WARNING ("subst_string: Loop exited after %zu iterations: "
-				"string = %s; needle = %s; replacement = %s;",
-				i, string, needle, replacement);
-	}
-
-	sfree (temp);
-	return (buf);
+char *subst_string(char *buf, size_t buflen, const char *string,
+                   const char *needle, const char *replacement) {
+  size_t needle_len;
+  size_t i;
+
+  if ((buf == NULL) || (string == NULL) || (needle == NULL) ||
+      (replacement == NULL))
+    return NULL;
+
+  needle_len = strlen(needle);
+  sstrncpy(buf, string, buflen);
+
+  /* Limit the loop to prevent endless loops. */
+  for (i = 0; i < buflen; i++) {
+    char temp[buflen];
+    char *begin_ptr;
+    size_t begin;
+
+    /* Find `needle' in `buf'. */
+    begin_ptr = strstr(buf, needle);
+    if (begin_ptr == NULL)
+      break;
+
+    /* Calculate the start offset. */
+    begin = begin_ptr - buf;
+
+    /* Substitute the region using `subst'. The result is stored in
+     * `temp'. */
+    begin_ptr =
+        subst(temp, buflen, buf, begin, begin + needle_len, replacement);
+    if (begin_ptr == NULL) {
+      WARNING("subst_string: subst failed.");
+      break;
+    }
+
+    /* Copy the new string in `temp' to `buf' for the next round. */
+    strncpy(buf, temp, buflen);
+  }
+
+  if (i >= buflen) {
+    WARNING("subst_string: Loop exited after %zu iterations: "
+            "string = %s; needle = %s; replacement = %s;",
+            i, string, needle, replacement);
+  }
+
+  return buf;
 } /* char *subst_string */
-
-/* vim: set sw=4 ts=4 tw=78 noexpandtab : */
-