src/core/asprintf.c

   1 #include <stdint.h>
   2 #include <stddef.h>
   3 #include <stdlib.h>
   4 #include <stdio.h>
   5 #include <errno.h>
   6
   7 /**
   8  * Write a formatted string to newly allocated memory.
   9  *
  10  * @v strp              Pointer to hold allocated string
  11  * @v fmt               Format string
  12  * @v args              Arguments corresponding to the format string
  13  * @ret len             Length of formatted string
  14  */
  15 int vasprintf ( char **strp, const char *fmt, va_list args ) {
  16         size_t len;
  17         va_list args_tmp;
  18
  19         /* Calculate length needed for string */
  20         va_copy ( args_tmp, args );
  21         len = ( vsnprintf ( NULL, 0, fmt, args_tmp ) + 1 );
  22         va_end ( args_tmp );
  23
  24         /* Allocate and fill string */
  25         *strp = malloc ( len );
  26         if ( ! *strp )
  27                 return -ENOMEM;
  28         return vsnprintf ( *strp, len, fmt, args );
  29 }
  30
  31 /**
  32  * Write a formatted string to newly allocated memory.
  33  *
  34  * @v strp              Pointer to hold allocated string
  35  * @v fmt               Format string
  36  * @v ...               Arguments corresponding to the format string
  37  * @ret len             Length of formatted string
  38  */
  39 int asprintf ( char **strp, const char *fmt, ... ) {
  40         va_list args;
  41         int len;
  42
  43         va_start ( args, fmt );
  44         len = vasprintf ( strp, fmt, args );
  45         va_end ( args );
  46         return len;
  47 }