Rewrite sprintf_alloc.

[oweals/opkg-lede.git] / libopkg / sprintf_alloc.c

diff --git a/libopkg/sprintf_alloc.c b/libopkg/sprintf_alloc.c
index 08c56bfe11b2b041f75ea2837132fc6e6d8ef582..e2513ecee5fda05c59861f6d08d0205d71270faa 100644 (file)
--- a/libopkg/sprintf_alloc.c
+++ b/libopkg/sprintf_alloc.c
@@ -1,8 +1,6 @@
 /* sprintf_alloc.c -- like sprintf with memory allocation
 
-   Carl D. Worth
-
-   Copyright (C) 2001 University of Southern California
+   Copyright (C) 2010 Ubiq Technologies <graham.gower@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
@@ -20,46 +18,32 @@
 #include "sprintf_alloc.h"
 #include "libbb/libbb.h"
 
-int sprintf_alloc(char **str, const char *fmt, ...)
+void
+sprintf_alloc(char **str, const char *fmt, ...)
 {
        va_list ap;
        int n;
-       unsigned size = 100;
-
-       if (!str) {
-               opkg_msg(ERROR, "Internal error: str=NULL.\n");
-               return -1;
-       }
-       if (!fmt) {
-               opkg_msg(ERROR, "Internal error: fmt=NULL.\n");
-               return -1;
-       }
-
-       /* On x86_64 systems, any strings over 100 were segfaulting.
-          It seems that the ap needs to be reinitalized before every
-          use of the v*printf() functions. I pulled the functionality out
-          of vsprintf_alloc and combined it all here instead.
-       */
-
-
-       /* ripped more or less straight out of PRINTF(3) */
+       unsigned int size = 1;
 
        *str = xcalloc(1, size);
 
-       while (1) {
+       for (;;) {
                va_start(ap, fmt);
                n = vsnprintf (*str, size, fmt, ap);
                va_end(ap);
-               /* If that worked, return the size. */
-               if (n > -1 && n < size)
-                       return n;
-               /* Else try again with more space. */
-               if (n > -1)    /* glibc 2.1 */
-                       size = n+1; /* precisely what is needed */
-               else           /* glibc 2.0 */
-                       size *= 2;  /* twice the old size */
+
+               if (n < 0) {
+                       fprintf(stderr, "%s: encountered an output or encoding"
+                                       " error during vsnprintf.\n",
+                                       __FUNCTION__);
+                       exit(EXIT_FAILURE);
+               }
+
+               if (n < size)
+                       break;
+
+               /* Truncated, try again with more space. */
+               size = n+1;
                *str = xrealloc(*str, size);
        }
-
-       return -1; /* Just to be correct - it probably won't get here */
 }