From 8d7d7a57b31433fad9bcfb2bb21cfa5cd1090679 Mon Sep 17 00:00:00 2001
From: Peter Verthez <Peter.Verthez@advalvas.be>
Date: Sun, 8 Dec 2002 09:59:57 +0000
Subject: [PATCH] Some changes to safe_buffer structure.

---
 gedcom/buffer.c  | 34 +++++++++++++++++++++++-----------
 gedcom/buffer.h  | 19 ++++++++++++++++++-
 gedcom/message.c |  2 +-
 gedcom/write.c   |  2 +-
 4 files changed, 43 insertions(+), 14 deletions(-)

diff --git a/gedcom/buffer.c b/gedcom/buffer.c
index c09eaa5..6f807b1 100644
--- a/gedcom/buffer.c
+++ b/gedcom/buffer.c
@@ -33,8 +33,11 @@
 
 void reset_buffer(struct safe_buffer* b)
 {
-  if (b && b->buffer != NULL)
-    b->buffer[0] = '\0';
+  if (b && b->buffer != NULL) {
+    memset(b->buffer, 0, b->bufsize);
+    b->buf_end = b->buffer;
+    b->buflen  = 0;
+  }
 }
 
 void cleanup_buffer(struct safe_buffer *b)
@@ -50,6 +53,8 @@ void init_buffer(struct safe_buffer *b)
     if (b->buffer) {
       b->buffer[0] = '\0';
       b->bufsize = INITIAL_BUF_SIZE;
+      b->buf_end = b->buffer;
+      b->buflen  = 0;
       if (b->cleanup_func && atexit(b->cleanup_func) != 0) {
 	fprintf(stderr, _("Could not register buffer cleanup function"));
 	fprintf(stderr, "\n");
@@ -63,31 +68,38 @@ void init_buffer(struct safe_buffer *b)
   }
 }
 
+void grow_buffer(struct safe_buffer *b)
+{
+  b->bufsize *= 2;
+  b->buffer = realloc(b->buffer, b->bufsize);
+  b->buf_end = b->buffer + b->buflen;
+}
+
 int safe_buf_vappend(struct safe_buffer *b, const char *s, va_list ap)
 {
   int res = 0;
-  int len;
   init_buffer(b);
   if (b && b->buffer) {
-    len = strlen(b->buffer);
     while (1) {
-      char *buf_ptr = b->buffer + len;
-      int rest_size = b->bufsize - len;
+      int rest_size = b->bufsize - b->buflen;
       
 #if HAVE_VSNPRINTF
-      res = vsnprintf(buf_ptr, rest_size, s, ap);
+      res = vsnprintf(b->buf_end, rest_size, s, ap);
       
       if (res > -1 && res < rest_size) {
+	b->buf_end = b->buf_end + res;
+	b->buflen  = b->buflen + res;
 	break;
       }
-      else  {
-	b->bufsize *= 2;
-	b->buffer = realloc(b->buffer, b->bufsize);
+      else {
+	grow_buffer(b);
       }
 #else /* not HAVE_VSNPRINTF */
 #  if HAVE_VSPRINTF
 #     warning "Using VSPRINTF. Buffer overflow could happen!"
-      vsprintf(buf_ptr, s, ap);
+      res = vsprintf(b->buf_end, s, ap);
+      b->buf_end = b->buf_end + res;
+      b->buflen  = b->buflen + res;
       break;
 #  else /* not HAVE_VPRINTF */
 #     error "Your standard library has neither vsnprintf nor vsprintf defined. One of them is required!"
diff --git a/gedcom/buffer.h b/gedcom/buffer.h
index f51acff..8475e8c 100644
--- a/gedcom/buffer.h
+++ b/gedcom/buffer.h
@@ -29,16 +29,33 @@
 
 struct safe_buffer {
   char* buffer;
-  size_t bufsize;
+  size_t bufsize;  /* total size */
+  char* buf_end;
+  size_t buflen;   /* used size */
   void (*cleanup_func)(void);
 };
 
 void init_buffer(struct safe_buffer* b);
 void reset_buffer(struct safe_buffer* b);
 void cleanup_buffer(struct safe_buffer* b);
+void grow_buffer(struct safe_buffer* b);
 
 int safe_buf_vappend(struct safe_buffer* b, const char* s, va_list ap);
 int safe_buf_append(struct safe_buffer* b, const char* s, ...);
 char* get_buf_string(struct safe_buffer* b);
 
+#define SAFE_BUF_ADDCHAR(b, ch)                                               \
+  {                                                                           \
+    struct safe_buffer *buf = b;                                              \
+    char c = ch;                                                              \
+    if (buf && buf->buffer == NULL)                                           \
+      init_buffer(buf);                                                       \
+    if (buf && buf->buffer) {                                                 \
+      if (buf->buflen == buf->bufsize)                                        \
+	grow_buffer(buf);                                                     \
+      *buf->buf_end++ = c;                                                    \
+      buf->buflen++;                                                          \
+    }                                                                         \
+  }
+
 #endif /* __BUFFER_H */
diff --git a/gedcom/message.c b/gedcom/message.c
index 6943f60..3fe288b 100644
--- a/gedcom/message.c
+++ b/gedcom/message.c
@@ -27,7 +27,7 @@
 
 void cleanup_mess_buffer();
 
-struct safe_buffer mess_buffer = { NULL, 0, cleanup_mess_buffer };
+struct safe_buffer mess_buffer = { NULL, 0, NULL, 0, cleanup_mess_buffer };
 Gedcom_msg_handler msg_handler = NULL;
 
 void gedcom_set_message_handler(Gedcom_msg_handler func)
diff --git a/gedcom/write.c b/gedcom/write.c
index e74a571..e82fd62 100644
--- a/gedcom/write.c
+++ b/gedcom/write.c
@@ -61,7 +61,7 @@ const char* terminator[] = {
 
 void cleanup_write_buffer();
 
-struct safe_buffer write_buffer = { NULL, 0, cleanup_write_buffer };
+struct safe_buffer write_buffer = { NULL, 0, NULL, 0, cleanup_write_buffer };
 
 void cleanup_write_buffer()
 {
-- 
2.30.2