[PATCH 2/2] getopt.c: use fputs()/fputc() instead of fprintf() to, save code space

[Freddie Chopin]

This is another approach aiming to reduce code and RAM usage of 
getopt(). Using fputs()/fputc() makes the function about 200 bytes 
bigger than when using f[i]printf() (on ARMv7-M, Cortex-M3), but now 
getopt() and family have zero dependency on heavy-weight formatting 
functions.

Regards,
FCh
-------------- next part --------------
From 7b66269186dcd32c32cda4b9f67a336a0f626510 Mon Sep 17 00:00:00 2001
From: Freddie Chopin <freddie.chopin@gmail.com>
Date: Fri, 8 Nov 2013 20:35:00 +0100
Subject: [PATCH 2/2] getopt.c: use fputs()/fputc() instead of fprintf() to
 save code space

---
 newlib/libc/stdlib/getopt.c | 34 +++++++++++++++++++++-------------
 1 file changed, 21 insertions(+), 13 deletions(-)

diff --git a/newlib/libc/stdlib/getopt.c b/newlib/libc/stdlib/getopt.c
index c2bd060..7cd4207 100644
--- a/newlib/libc/stdlib/getopt.c
+++ b/newlib/libc/stdlib/getopt.c
@@ -177,7 +177,9 @@ write_globals (struct getopt_data *data)
   optwhere = data->optwhere;
 }
 
-/* getopt_internal:  the function that does all the dirty work */
+/* getopt_internal:  the function that does all the dirty work
+   NOTE: to reduce the code and RAM footprint this function uses
+   fputs()/fputc() to do output to stderr instead of fprintf(). */
 static int
 getopt_internal (int argc, char *const argv[], const char *shortopts,
 		 const struct option *longopts, int *longind, int only,
@@ -311,12 +313,14 @@ getopt_internal (int argc, char *const argv[], const char *shortopts,
 		    {
 		      /* we have ambiguous options */
 		      if (data->opterr)
-			fprintf (stderr, "%s: option `%s' is ambiguous "
-				 "(could be `--%s' or `--%s')\n",
-				 argv[0],
-				 argv[data->optind],
-				 longopts[longopt_match].name,
-				 longopts[optindex].name);
+			fputs (argv[0], stderr);
+			fputs (": option `", stderr);
+			fputs (argv[data->optind], stderr);
+			fputs ("' is ambiguous (could be `--", stderr);
+			fputs (longopts[longopt_match].name, stderr);
+			fputs ("' or `--", stderr);
+			fputs (longopts[optindex].name, stderr);
+			fputs ("')\n", stderr);
 		      return (data->optopt = '?');
 		    }
 		}
@@ -334,9 +338,10 @@ getopt_internal (int argc, char *const argv[], const char *shortopts,
 	{
 	  /* couldn't find option in shortopts */
 	  if (data->opterr)
-	    fprintf (stderr,
-		     "%s: invalid option -- `-%c'\n",
-		     argv[0], argv[data->optind][data->optwhere]);
+	    fputs (argv[0], stderr);
+	    fputs (": invalid option -- `-", stderr);
+	    fputc (argv[data->optind][data->optwhere], stderr);
+	    fputs ("'\n", stderr);
 	  data->optwhere++;
 	  if (argv[data->optind][data->optwhere] == '\0')
 	    {
@@ -373,17 +378,20 @@ getopt_internal (int argc, char *const argv[], const char *shortopts,
 	{
 	  if (data->opterr)
 	    {
-	      fprintf (stderr, "%s: argument required for option `", argv[0]);
+	      fputs (argv[0], stderr);
+	      fputs (": argument required for option `-", stderr);
 	      if (longopt_match >= 0)
 		{
-		  fprintf (stderr, "--%s'\n", longopts[longopt_match].name);
+		  fputc ('-', stderr);
+		  fputs (longopts[longopt_match].name, stderr);
 		  data->optopt = initial_colon ? ':' : '\?';
 		}
 	      else
 		{
-		  fprintf (stderr, "-%c'\n", *cp);
+		  fputc (*cp, stderr);
 		  data->optopt = *cp;
 		}
+	      fputs ("'\n", stderr);
 	    }
 	  data->optind++;
 	  return initial_colon ? ':' : '\?';
-- 
1.8.3.msysgit.0