vfprintf: Introduce printf_positional function

This splits a considerable chunk of code from the main vfprintf
function.  This will make it easier to remove the use of extend_alloca
from the positional argument handling code.

ChangeLog

@@ -1,3 +1,10 @@
+2015-05-21  Florian Weimer  <fweimer@redhat.com>
+
+	* stdio-common/vfprintf.c (vfprintf): Move local variables
+	args_malloced, specs, specs_malloced, and the code after
+	do_positional to the printf_positional function.
+	(printf_positional): New function.
+
 2015-05-21  Florian Weimer  <fweimer@redhat.com>
 
 	* stdio-common/vfprintf.c (jump_table): Move out of the vfprintf

stdio-common/vfprintf.c

@@ -1209,6 +1209,14 @@ static const uint8_t jump_table[] =
 static int buffered_vfprintf (FILE *stream, const CHAR_T *fmt, va_list)
      __THROW __attribute__ ((noinline)) internal_function;
 
+/* Handle positional format specifiers.  */
+static int printf_positional (_IO_FILE *s,
+			      const CHAR_T *format, int readonly_format,
+			      va_list ap, va_list *ap_savep, int done,
+			      int nspecs_done, const UCHAR_T *lead_str_end,
+			      CHAR_T *work_buffer, int save_errno,
+			      const char *grouping, THOUSANDS_SEP_T);
+
 /* Handle unknown format specifier.  */
 static int printf_unknown (FILE *, const struct printf_info *,
 			   const void *const *) __THROW;
@@ -1257,15 +1265,6 @@ vfprintf (FILE *s, const CHAR_T *format, va_list ap)
      0 if unknown.  */
   int readonly_format = 0;
 
-  /* For the argument descriptions, which may be allocated on the heap.  */
-  void *args_malloced = NULL;
-
-  /* For positional argument handling.  */
-  struct printf_spec *specs;
-
-  /* Track if we malloced the SPECS array and thus must free it.  */
-  bool specs_malloced = false;
-
   /* Orient the stream.  */
 #ifdef ORIENT
   ORIENT;
@@ -1670,9 +1669,43 @@ vfprintf (FILE *s, const CHAR_T *format, va_list ap)
   /* Unlock stream and return.  */
   goto all_done;
 
-  /* Here starts the more complex loop to handle positional parameters.  */
+  /* Hand off processing for positional parameters.  */
 do_positional:
+  if (__glibc_unlikely (workstart != NULL))
     {
+      free (workstart);
+      workstart = NULL;
+    }
+  done = printf_positional (s, format, readonly_format, ap, &ap_save,
+			    done, nspecs_done, lead_str_end, work_buffer,
+			    save_errno, grouping, thousands_sep);
+
+ all_done:
+  if (__glibc_unlikely (workstart != NULL))
+    free (workstart);
+  /* Unlock the stream.  */
+  _IO_funlockfile (s);
+  _IO_cleanup_region_end (0);
+
+  return done;
+}
+
+static int
+printf_positional (_IO_FILE *s, const CHAR_T *format, int readonly_format,
+		   va_list ap, va_list *ap_savep, int done, int nspecs_done,
+		   const UCHAR_T *lead_str_end,
+		   CHAR_T *work_buffer, int save_errno,
+		   const char *grouping, THOUSANDS_SEP_T thousands_sep)
+{
+  /* For the argument descriptions, which may be allocated on the heap.  */
+  void *args_malloced = NULL;
+
+  /* For positional argument handling.  */
+  struct printf_spec *specs;
+
+  /* Track if we malloced the SPECS array and thus must free it.  */
+  bool specs_malloced = false;
+
   /* Array with information about the needed arguments.  This has to
      be dynamically extensible.  */
   size_t nspecs = 0;
@@ -1697,9 +1730,7 @@ do_positional:
   /* Just a counter.  */
   size_t cnt;
 
-    if (__glibc_unlikely (workstart != NULL))
+  CHAR_T *workstart = NULL;
-      free (workstart);
-    workstart = NULL;
 
   if (grouping == (const char *) -1)
     {
@@ -1715,7 +1746,8 @@ do_positional:
 	grouping = NULL;
     }
 
-    for (f = lead_str_end; *f != L_('\0'); f = specs[nspecs++].next_fmt)
+  for (const UCHAR_T *f = lead_str_end; *f != L_('\0');
+       f = specs[nspecs++].next_fmt)
     {
       if (nspecs * sizeof (*specs) >= nspecs_size)
 	{
@@ -1841,7 +1873,7 @@ do_positional:
       {
 #define T(tag, mem, type)				\
 	case tag:					\
-	  args_value[cnt].mem = va_arg (ap_save, type);			      \
+	  args_value[cnt].mem = va_arg (*ap_savep, type); \
 	  break
 
 	T (PA_WCHAR, pa_wchar, wint_t);
@@ -1863,11 +1895,11 @@ do_positional:
       case PA_DOUBLE|PA_FLAG_LONG_DOUBLE:
 	if (__ldbl_is_dbl)
 	  {
-	      args_value[cnt].pa_double = va_arg (ap_save, double);
+	    args_value[cnt].pa_double = va_arg (*ap_savep, double);
 	    args_type[cnt] &= ~PA_FLAG_LONG_DOUBLE;
 	  }
 	else
-	    args_value[cnt].pa_long_double = va_arg (ap_save, long double);
+	  args_value[cnt].pa_long_double = va_arg (*ap_savep, long double);
 	break;
       case PA_STRING:				/* All pointers are the same */
       case PA_WSTRING:			/* All pointers are the same */
@@ -1875,13 +1907,13 @@ do_positional:
 #undef T
       default:
 	if ((args_type[cnt] & PA_FLAG_PTR) != 0)
-	    args_value[cnt].pa_pointer = va_arg (ap_save, void *);
+	  args_value[cnt].pa_pointer = va_arg (*ap_savep, void *);
 	else if (__glibc_unlikely (__printf_va_arg_table != NULL)
 		 && __printf_va_arg_table[args_type[cnt] - PA_LAST] != NULL)
 	  {
 	    args_value[cnt].pa_user = alloca (args_size[cnt]);
 	    (*__printf_va_arg_table[args_type[cnt] - PA_LAST])
-		(args_value[cnt].pa_user, &ap_save);
+	      (args_value[cnt].pa_user, ap_savep);
 	  }
 	else
 	  args_value[cnt].pa_long_double = 0.0;
@@ -1935,7 +1967,7 @@ do_positional:
       CHAR_T spec = specs[nspecs_done].info.spec;
 
       workstart = NULL;
-	workend = work_buffer + WORK_BUFFER_SIZE;
+      CHAR_T *workend = work_buffer + WORK_BUFFER_SIZE;
 
       /* Fill in last information.  */
       if (specs[nspecs_done].width_arg != -1)
@@ -2071,19 +2103,9 @@ do_positional:
 		 specs[nspecs_done].next_fmt
 		 - specs[nspecs_done].end_of_fmt);
     }
-  }
+ all_done:
-
-all_done:
-  if (specs_malloced)
-    free (specs);
-  if (__glibc_unlikely (args_malloced != NULL))
-    free (args_malloced);
   if (__glibc_unlikely (workstart != NULL))
     free (workstart);
-  /* Unlock the stream.  */
-  _IO_funlockfile (s);
-  _IO_cleanup_region_end (0);
-
   return done;
 }