X-Git-Url: http://mj.ucw.cz/gitweb/?a=blobdiff_plain;ds=sidebyside;f=lib%2Fmempool-fmt.c;h=397a7721da18c473505da893f49dd50e72fee7cb;hb=1d8112cb590e458baa899805908a8ac910f58163;hp=c8b1e4c823ecb9d04f81a6adf391e4e0d102a894;hpb=2860df435bc0ec1601bf2e7eedacc63258b932aa;p=libucw.git

diff --git a/lib/mempool-fmt.c b/lib/mempool-fmt.c
index c8b1e4c8..397a7721 100644
--- a/lib/mempool-fmt.c
+++ b/lib/mempool-fmt.c
@@ -2,6 +2,7 @@
  *	UCW Library -- Memory Pools (Formatting)
  *
  *	(c) 2005 Martin Mares <mj@ucw.cz>
+ *	(c) 2007 Pavel Charvat <pchar@ucw.cz>
  *
  *	This software may be freely distributed and used according to the terms
  *	of the GNU Lesser General Public License.
@@ -14,45 +15,47 @@
 #include <stdio.h>
 #include <string.h>
 
-char *
-mp_vprintf(struct mempool *p, char *fmt, va_list args)
+static char *
+mp_vprintf_at(struct mempool *mp, uns ofs, const char *fmt, va_list args)
 {
-  char *ret = p->free;
-  int free = p->last - p->free;
-  if (!free)
-    {
-      ret = mp_alloc(p, 1);
-      free = p->last - p->free;
-    }
-  int cnt = vsnprintf(ret, free, fmt, args);
+  char *ret = mp_grow(mp, ofs + 1) + ofs;
+  va_list args2;
+  va_copy(args2, args);
+  int cnt = vsnprintf(ret, mp_avail(mp) - ofs, fmt, args2);
+  va_end(args2);
   if (cnt < 0)
     {
       /* Our C library doesn't support C99 return value of vsnprintf, so we need to iterate */
-      uns len = 128;
-      char *buf;
       do
 	{
-	  len *= 2;
-	  buf = alloca(len);
-	  cnt = vsnprintf(buf, len, fmt, args);
+	  ret = mp_expand(mp) + ofs;
+	  va_copy(args2, args);
+	  cnt = vsnprintf(ret, mp_avail(mp) - ofs, fmt, args2);
+	  va_end(args2);
 	}
       while (cnt < 0);
-      ret = mp_alloc(p, cnt+1);
-      memcpy(ret, buf, cnt+1);
     }
-  else if (cnt < free)
-    p->free += cnt + 1;
-  else
+  else if ((uns)cnt >= mp_avail(mp) - ofs)
     {
-      ret = mp_alloc(p, cnt+1);
-      int cnt2 = vsnprintf(ret, cnt+1, fmt, args);
+      ret = mp_grow(mp, cnt + 1) + ofs;
+      va_copy(args2, args);
+      int cnt2 = vsnprintf(ret, cnt + 1, fmt, args2);
+      va_end(args2);
       ASSERT(cnt2 == cnt);
     }
-  return ret;
+  mp_end(mp, ret + cnt + 1);
+  return ret - ofs;
+}
+
+char *
+mp_vprintf(struct mempool *mp, const char *fmt, va_list args)
+{
+  mp_start(mp, 1);
+  return mp_vprintf_at(mp, 0, fmt, args);
 }
 
 char *
-mp_printf(struct mempool *p, char *fmt, ...)
+mp_printf(struct mempool *p, const char *fmt, ...)
 {
   va_list args;
   va_start(args, fmt);
@@ -61,6 +64,24 @@ mp_printf(struct mempool *p, char *fmt, ...)
   return res;
 }
 
+char *
+mp_vprintf_append(struct mempool *mp, char *ptr, const char *fmt, va_list args)
+{
+  uns ofs = mp_open(mp, ptr);
+  ASSERT(ofs);
+  return mp_vprintf_at(mp, ofs - 1, fmt, args);
+}
+
+char *
+mp_printf_append(struct mempool *mp, char *ptr, const char *fmt, ...)
+{
+  va_list args;
+  va_start(args, fmt);
+  char *res = mp_vprintf_append(mp, ptr, fmt, args);
+  va_end(args);
+  return res;
+}
+
 #ifdef TEST
 
 int main(void)
@@ -68,6 +89,8 @@ int main(void)
   struct mempool *mp = mp_new(64);
   char *x = mp_printf(mp, "<Hello, %s!>", "World");
   fputs(x, stdout);
+  x = mp_printf_append(mp, x, "<Appended>");
+  fputs(x, stdout);
   x = mp_printf(mp, "<Hello, %50s!>\n", "World");
   fputs(x, stdout);
   return 0;