From: Kevin McCarthy <kevin@8t8.us>
Date: Sun, 10 Mar 2019 01:58:07 +0000 (+0800)
Subject: Minor buffer handling code cleanup.
X-Git-Tag: mutt-1-12-rel~100
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=5be5ad46119377f425181d3079c5700ef4bd33e0;p=mutt

Minor buffer handling code cleanup.

Use mutt_buffer_len() and mutt_buffer_clear() to make the code a bit
clearer.  There are still places in the code that manipulate the
buffers directly (pattern.c, for example), but that doesn't mean we
shouldn't abstract the buffer where we can.

Add comments in a couple places where unusual buffer manipulation is
occurring.
---

diff --git a/base64.c b/base64.c
index d942e546..67e13c30 100644
--- a/base64.c
+++ b/base64.c
@@ -93,6 +93,7 @@ int mutt_buffer_from_base64 (BUFFER *out, const char *in)
 
   mutt_buffer_increase_size (out, mutt_strlen (in));
   olen = mutt_from_base64 (out->data, in, out->dsize);
+  /* mutt_from_base64 returns raw bytes, so don't terminate the buffer either */
   if (olen > 0)
     out->dptr = out->data + olen;
   else
diff --git a/imap/command.c b/imap/command.c
index 175ae5c8..1494088c 100644
--- a/imap/command.c
+++ b/imap/command.c
@@ -448,12 +448,12 @@ static int cmd_start (IMAP_DATA* idata, const char* cmdstr, int flags)
   if (flags & IMAP_CMD_QUEUE)
     return 0;
 
-  if (idata->cmdbuf->dptr == idata->cmdbuf->data)
+  if (mutt_buffer_len (idata->cmdbuf) == 0)
     return IMAP_CMD_BAD;
 
   rc = mutt_socket_write_d (idata->conn, idata->cmdbuf->data, -1,
                             flags & IMAP_CMD_PASS ? IMAP_LOG_PASS : IMAP_LOG_CMD);
-  idata->cmdbuf->dptr = idata->cmdbuf->data;
+  mutt_buffer_clear (idata->cmdbuf);
 
   /* unidle when command queue is flushed */
   if (idata->state == IMAP_IDLE)
diff --git a/imap/imap.c b/imap/imap.c
index f9ce4957..4764698a 100644
--- a/imap/imap.c
+++ b/imap/imap.c
@@ -973,7 +973,7 @@ static int imap_make_msg_set (IMAP_DATA* idata, BUFFER* buf, int flag,
   hdrs = idata->ctx->hdrs;
 
   for (n = *pos;
-       n < idata->ctx->msgcount && buf->dptr - buf->data < IMAP_MAX_CMDLEN;
+       (n < idata->ctx->msgcount) && (mutt_buffer_len (buf) < IMAP_MAX_CMDLEN);
        n++)
   {
     match = 0;
@@ -1086,7 +1086,7 @@ int imap_exec_msgset (IMAP_DATA* idata, const char* pre, const char* post,
 
   do
   {
-    cmd->dptr = cmd->data;
+    mutt_buffer_clear (cmd);
     mutt_buffer_add_printf (cmd, "%s ", pre);
     rc = imap_make_msg_set (idata, cmd, flag, changed, invert, &pos);
     if (rc > 0)
@@ -1153,7 +1153,7 @@ int imap_sync_message_for_copy (IMAP_DATA *idata, HEADER *hdr, BUFFER *cmd,
   }
 
   snprintf (uid, sizeof (uid), "%u", HEADER_DATA(hdr)->uid);
-  cmd->dptr = cmd->data;
+  mutt_buffer_clear (cmd);
   mutt_buffer_addstr (cmd, "UID STORE ");
   mutt_buffer_addstr (cmd, uid);
 
diff --git a/imap/message.c b/imap/message.c
index 95b8366a..47904f58 100644
--- a/imap/message.c
+++ b/imap/message.c
@@ -185,7 +185,7 @@ static void imap_fetch_msn_seqset (BUFFER *b, IMAP_DATA *idata, unsigned int msn
   /* Too big.  Just query the whole range then. */
   if (chunks == 150 || mutt_strlen (b->data) > 500)
   {
-    b->dptr = b->data;
+    mutt_buffer_clear (b);
     mutt_buffer_add_printf (b, "%u:%u", msn_begin, msn_end);
   }
 }
diff --git a/init.c b/init.c
index fe75c2db..387fde15 100644
--- a/init.c
+++ b/init.c
@@ -140,8 +140,7 @@ int mutt_extract_token (BUFFER *dest, BUFFER *tok, int flags)
   char		qc = 0; /* quote char */
   char		*pc;
 
-  /* reset the destination pointer to the beginning of the buffer */
-  dest->dptr = dest->data;
+  mutt_buffer_clear (dest);
 
   SKIPWS (tok->dptr);
   while ((ch = *tok->dptr))
@@ -3406,9 +3405,7 @@ void mutt_init (int skip_sys_rc, LIST *commands)
   BUFFER err;
 
   mutt_buffer_init (&err);
-  err.dsize = STRING;
-  err.data = safe_malloc(err.dsize);
-  err.dptr = err.data;
+  mutt_buffer_increase_size (&err, STRING);
 
   Groups = hash_create (1031, 0);
   /* reverse alias keys need to be strdup'ed because of idna conversions */
diff --git a/muttlib.c b/muttlib.c
index 191c1df7..f458e7ac 100644
--- a/muttlib.c
+++ b/muttlib.c
@@ -1275,6 +1275,8 @@ void mutt_FormatString (char *dest,		/* output buffer */
 
       /* prepare BUFFERs */
       srcbuf = mutt_buffer_from (srccopy);
+      /* note: we are resetting dptr and *reading* from the buffer, so we don't
+       * want to use mutt_buffer_clear(). */
       srcbuf->dptr = srcbuf->data;
       word = mutt_buffer_new ();
       command = mutt_buffer_new ();
diff --git a/parse.c b/parse.c
index c243062c..47e0f084 100644
--- a/parse.c
+++ b/parse.c
@@ -1447,8 +1447,7 @@ ENVELOPE *mutt_read_rfc822_header (FILE *f, HEADER *hdr, short user_hdrs,
 	  /* else overwrite */
 	  else
 	  {
-	    e->spam->dptr = e->spam->data;
-	    *e->spam->dptr = '\0';
+            mutt_buffer_clear (e->spam);
 	    mutt_buffer_addstr(e->spam, buf);
 	  }
 	}