pingpong.c: fix Curl_pp_vsendf() arbitrary restrictions on command length

This removes command length restrictions on calling functions.

lib/imap.c

@@ -210,9 +210,6 @@ static const struct Curl_handler Curl_handler_imaps_proxy = {
  *
  * Sends the formated string as an IMAP command to a server
  *
- * NOTE: we build the command in a fixed-length buffer, which sets length
- * restrictions on the command!
- *
  * Designed to never block.
  */
 static CURLcode imapsendf(struct connectdata *conn,

lib/pingpong.c

@@ -177,9 +177,6 @@ void Curl_pp_init(struct pingpong *pp)
  * the string should not have any CRLF appended, as this function will
  * append the necessary things itself.
  *
- * NOTE: we build the command in a fixed-length buffer, which sets length
- * restrictions on the command!
- *
  * made to never block
  */
 CURLcode Curl_pp_vsendf(struct pingpong *pp,
@@ -187,12 +184,10 @@ CURLcode Curl_pp_vsendf(struct pingpong *pp,
                         va_list args)
 {
   ssize_t bytes_written;
-/* may still not be big enough for some krb5 tokens */
-#define SBUF_SIZE 1024
-  char s[SBUF_SIZE];
   size_t write_len;
-  char *sptr=s;
-  CURLcode res = CURLE_OK;
+  char *fmt_crlf;
+  char *s;
+  CURLcode error;
   struct connectdata *conn = pp->conn;
   struct SessionHandle *data = conn->data;
 
@@ -200,55 +195,61 @@ CURLcode Curl_pp_vsendf(struct pingpong *pp,
   enum protection_level data_sec = conn->data_prot;
 #endif
 
-  vsnprintf(s, SBUF_SIZE-3, fmt, args);
+  fmt_crlf = aprintf("%s\r\n", fmt); /* append a trailing CRLF */
+  if(!fmt_crlf)
+    return CURLE_OUT_OF_MEMORY;
 
-  strcat(s, "\r\n"); /* append a trailing CRLF */
+  s = vaprintf(fmt_crlf, args); /* trailing CRLF appended */
+  free(fmt_crlf);
+  if(!s)
+    return CURLE_OUT_OF_MEMORY;
 
-  bytes_written=0;
+  bytes_written = 0;
   write_len = strlen(s);
 
   Curl_pp_init(pp);
 
-  res = Curl_convert_to_network(data, s, write_len);
+  error = Curl_convert_to_network(data, s, write_len);
   /* Curl_convert_to_network calls failf if unsuccessful */
-  if(res)
-    return res;
+  if(error) {
+    free(s);
+    return error;
+  }
 
 #if defined(HAVE_KRB4) || defined(HAVE_GSSAPI)
   conn->data_prot = PROT_CMD;
 #endif
-  res = Curl_write(conn, conn->sock[FIRSTSOCKET], sptr, write_len,
+  error = Curl_write(conn, conn->sock[FIRSTSOCKET], s, write_len,
                      &bytes_written);
 #if defined(HAVE_KRB4) || defined(HAVE_GSSAPI)
   DEBUGASSERT(data_sec > PROT_NONE && data_sec < PROT_LAST);
   conn->data_prot = data_sec;
 #endif
 
-  if(CURLE_OK != res)
-    return res;
+  if(error) {
+    free(s);
+    return error;
+  }
 
   if(conn->data->set.verbose)
     Curl_debug(conn->data, CURLINFO_HEADER_OUT,
-               sptr, (size_t)bytes_written, conn);
+               s, (size_t)bytes_written, conn);
 
   if(bytes_written != (ssize_t)write_len) {
     /* the whole chunk was not sent, store the rest of the data */
     write_len -= bytes_written;
-    sptr += bytes_written;
-    pp->sendthis = malloc(write_len);
-    if(pp->sendthis) {
-      memcpy(pp->sendthis, sptr, write_len);
+    memmove(s, s + bytes_written, write_len + 1);
+    pp->sendthis = s;
     pp->sendsize = pp->sendleft = write_len;
   }
   else {
-      failf(data, "out of memory");
-      res = CURLE_OUT_OF_MEMORY;
-    }
-  }
-  else
+    free(s);
+    pp->sendthis = NULL;
+    pp->sendleft = pp->sendsize = 0;
     pp->response = Curl_tvnow();
+  }
 
-  return res;
+  return CURLE_OK;
 }
 
 
@@ -260,9 +261,6 @@ CURLcode Curl_pp_vsendf(struct pingpong *pp,
  * the string should not have any CRLF appended, as this function will
  * append the necessary things itself.
  *
- * NOTE: we build the command in a fixed-length buffer, which sets length
- * restrictions on the command!
- *
  * made to never block
  */
 CURLcode Curl_pp_sendf(struct pingpong *pp,

lib/pingpong.h

@@ -98,9 +98,6 @@ long Curl_pp_state_timeout(struct pingpong *pp);
  * the string should not have any CRLF appended, as this function will
  * append the necessary things itself.
  *
- * NOTE: we build the command in a fixed-length buffer, which sets length
- * restrictions on the command!
- *
  * made to never block
  */
 CURLcode Curl_pp_sendf(struct pingpong *pp,
@@ -114,9 +111,6 @@ CURLcode Curl_pp_sendf(struct pingpong *pp,
  * the string should not have any CRLF appended, as this function will
  * append the necessary things itself.
  *
- * NOTE: we build the command in a fixed-length buffer, which sets length
- * restrictions on the command!
- *
  * made to never block
  */
 CURLcode Curl_pp_vsendf(struct pingpong *pp,