if (result < 0 || (size_t)result >= buffersize)
{
buffer[buffersize - 1] = '\0';
+ // we could be inside Con_Printf
+ if (result < 0)
+ Sys_Printf("dpvsnprintf: output error, buffer size %zu\n", buffersize);
+ else
+ Sys_Printf("dpvsnprintf: truncated to %zu bytes: \"%s\"\n", buffersize - 1, buffer);
return -1;
}
#undef APPEND
}
-//========================================================
-// strlcat and strlcpy, from OpenBSD
/*
- * Copyright (c) 1998, 2015 Todd C. Miller <millert@openbsd.org>
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- */
-
-/* $OpenBSD: strlcat.c,v 1.19 2019/01/25 00:19:25 millert Exp $ */
-/* $OpenBSD: strlcpy.c,v 1.16 2019/01/25 00:19:25 millert Exp $ */
+============
+String Copying
+The glibc implementation of memccpy is several times faster than old functions that
+copy one byte at a time (even at -O3) and its advantage increases with string length.
+============
+*/
+#ifdef WIN32
+ // memccpy() is standard in POSIX.1-2001, POSIX.1-2008, SVr4, 4.3BSD, C23.
+ // Microsoft supports it, but apparently complains if we use it.
+ #pragma warning(disable : 4996)
+#endif
-#ifndef HAVE_STRLCAT
-size_t
-strlcat(char *dst, const char *src, size_t dsize)
+/** Chain-copies a string with truncation and efficiency (compared to strlcat()).
+ * The destination ends at an absolute pointer instead of a relative offset
+ * and a pointer to the \0 terminator is returned on success.
+ * Truncates, warns, and returns the end pointer on overflow or unterminated source.
+ * Guarantees \0 termination. end = dst + sizeof(src[])
+ */
+char *dp_stpecpy(char *dst, char *end, const char *src)
{
- const char *odst = dst;
- const char *osrc = src;
- size_t n = dsize;
- size_t dlen;
-
- /* Find the end of dst and adjust bytes left but don't go past end. */
- while (n-- != 0 && *dst != '\0')
- dst++;
- dlen = dst - odst;
- n = dsize - dlen;
-
- if (n-- == 0)
- return(dlen + strlen(src));
- while (*src != '\0') {
- if (n != 0) {
- *dst++ = *src;
- n--;
- }
- src++;
- }
- *dst = '\0';
+ char *p = (char *)memccpy(dst, src, '\0', end - dst);
- return(dlen + (src - osrc)); /* count does not include NUL */
+ if (p)
+ return p - 1;
+ end[-1] = '\0';
+ Con_Printf(CON_WARN "%s: src string unterminated or truncated to %zu bytes: \"%s\"\n", __func__, dst == end ? 0 : (end - dst) - 1, dst);
+ return end;
}
-#endif // #ifndef HAVE_STRLCAT
+/** Copies a measured byte sequence (unterminated string) to a null-terminated string.
+ * Returns a pointer to the \0 terminator. Guarantees \0 termination.
+ * Compared to ustr2stp(): truncates and warns on overflow.
+ */
+char *dp_ustr2stp(char *dst, size_t dsize, const char *src, size_t ssize)
+{
+ if (ssize >= dsize)
+ {
+ ssize = dsize - 1;
+ Con_Printf(CON_WARN "%s: src string truncated to %zu bytes: \"%.*s\"\n", __func__, ssize, (int)ssize, src);
+ }
+ memcpy(dst, src, ssize);
+ dst[ssize] = '\0';
+ return &dst[ssize];
+}
-#ifndef HAVE_STRLCPY
-size_t
-strlcpy(char *dst, const char *src, size_t dsize)
+/** Copies a string, like strlcpy() but with a better return: the number of bytes copied
+ * excluding the \0 terminator. Truncates and warns on overflow or unterminated source,
+ * whereas strlcpy() truncates silently and overreads (possibly segfaulting).
+ * Guarantees \0 termination.
+ * See also: dp_stpecpy() and dp_ustr2stp().
+ */
+size_t dp__strlcpy(char *dst, const char *src, size_t dsize, const char *func, unsigned line)
{
- const char *osrc = src;
- size_t nleft = dsize;
+ char *p = (char *)memccpy(dst, src, '\0', dsize);
- /* Copy as many bytes as will fit. */
- if (nleft != 0) {
- while (--nleft != 0) {
- if ((*dst++ = *src++) == '\0')
- break;
- }
- }
+ if (p)
+ return (p - 1) - dst;
+ dst[dsize - 1] = '\0';
+ Con_Printf(CON_WARN "%s:%u: src string unterminated or truncated to %zu bytes: \"%s\"\n", func, line, dsize - 1, dst);
+ return dsize - 1;
+}
- /* Not enough room in dst, add NUL and traverse rest of src. */
- if (nleft == 0) {
- if (dsize != 0)
- *dst = '\0'; /* NUL-terminate dst */
- while (*src++)
- ;
- }
+/** Catenates a string, like strlcat() but with a better return: the number of bytes copied
+ * excluding the \0 terminator. Truncates and warns on overflow or unterminated source,
+ * whereas strlcat() truncates silently and overreads (possibly segfaulting).
+ * Guarantees \0 termination.
+ * Inefficient like any strcat(), please use memcpy(), dp_stpecpy() or dp_strlcpy() instead.
+ */
+size_t dp__strlcat(char *dst, const char *src, size_t dsize, const char *func, unsigned line)
+{
+ char *p = (char *)memchr(dst, '\0', dsize) ?: dst;
+ size_t offset = p - dst;
- return(src - osrc - 1); /* count does not include NUL */
+ return dp__strlcpy(p, src, dsize - offset, func, line) + offset;
}
-#endif // #ifndef HAVE_STRLCPY
+
void FindFraction(double val, int *num, int *denom, int denomMax)
{
while(COM_ParseToken_QuakeC(&in, false))
{
tokens[line] = lines[line];
- strlcpy(lines[line++], com_token, sizeof(lines[0]));
+ dp_strlcpy(lines[line++], com_token, sizeof(lines[0]));
if(!COM_ParseToken_QuakeC(&in, false))
return NULL;
if(!strcmp(com_token, "}"))
projects / xonotic / darkplaces.git / blobdiff