Prefer "STREQ (a, b)" over "strcmp (a, b) == 0"; similar for != 0.

* src/base64.c (main): Likewise.
* src/install.c (setdefaultfilecon): Likewise.
* src/sort.c (main): Likewise.
* Makefile.maint (sc_prohibit_strcmp): New rule.
* .x-sc_prohibit_strcmp: New file, to list the few exceptions.
* Makefile.am (EXTRA_DIST): Add .x-sc_prohibit_strcmp.

.x-sc_prohibit_strcmp

@@ -0,0 +1,2 @@
+^src/system\.h
+ChangeLog

ChangeLog

@@ -1,3 +1,13 @@
+2007-06-23  Jim Meyering  <jim@meyering.net>
+
+	Prefer "STREQ (a, b)" over "strcmp (a, b) == 0"; similar for != 0.
+	* src/base64.c (main): Likewise.
+	* src/install.c (setdefaultfilecon): Likewise.
+	* src/sort.c (main): Likewise.
+	* Makefile.maint (sc_prohibit_strcmp): New rule.
+	* .x-sc_prohibit_strcmp: New file, to list the few exceptions.
+	* Makefile.am (EXTRA_DIST): Add .x-sc_prohibit_strcmp.
+
 2007-06-22  Paul Eggert  <eggert@cs.ucla.edu>
 
 	* NEWS: seq no longer mishandles obvious cases like

Makefile.am

@@ -26,6 +26,7 @@ EXTRA_DIST = Makefile.cfg Makefile.maint GNUmakefile \
   .x-po-check \
   .x-sc_file_system .x-sc_obsolete_symbols \
   .x-sc_prohibit_atoi_atof \
+  .x-sc_prohibit_strcmp \
   .x-sc_require_config_h \
   .x-sc_space_tab .x-sc_sun_os_names \
   .x-sc_trailing_blank \

Makefile.maint

@@ -125,6 +125,13 @@ sc_prohibit_atoi_atof:
 	  { echo '$(ME): do not use *scan''f, ato''f, ato''i, ato''l, ato''ll, ato''q, or ss''canf'	\
 		1>&2; exit 1; } || :
 
+# Use STREQ rather than comparing strcmp == 0, or != 0.
+sc_prohibit_strcmp:
+	@grep -nE '! *str''cmp \(|\<str''cmp \([^)]+\) *==' \
+	    $$($(CVS_LIST_EXCEPT)) && \
+	  { echo '$(ME): use STREQ in place of the above uses of str''cmp' \
+		1>&2; exit 1; } || :
+
 # Using EXIT_SUCCESS as the first argument to error is misleading,
 # since when that parameter is 0, error does not exit.  Use `0' instead.
 sc_error_exit_success:

src/base64.c

@@ -296,7 +296,7 @@ main (int argc, char **argv)
   else
     infile = "-";
 
-  if (strcmp (infile, "-") == 0)
+  if (STREQ (infile, "-"))
     input_fh = stdin;
   else
     {
@@ -312,7 +312,7 @@ main (int argc, char **argv)
 
   if (fclose (input_fh) == EOF)
     {
-      if (strcmp (infile, "-") == 0)
+      if (STREQ (infile, "-"))
 	error (EXIT_FAILURE, errno, _("closing standard input"));
       else
 	error (EXIT_FAILURE, errno, "%s", infile);

src/install.c

@@ -217,7 +217,7 @@ setdefaultfilecon (char const *file)
   /* If there's an error determining the context, or it has none,
      return to allow default context */
   if ((matchpathcon (file, st.st_mode, &scontext) != 0) ||
-      (strcmp (scontext, "<<none>>") == 0))
+      STREQ (scontext, "<<none>>"))
     {
       if (scontext != NULL)
 	freecon (scontext);

src/sort.c

@@ -2930,7 +2930,7 @@ main (int argc, char **argv)
 	  break;
 
 	case COMPRESS_PROGRAM_OPTION:
-	  if (compress_program && strcmp (compress_program, optarg) != 0)
+	  if (compress_program && !STREQ (compress_program, optarg))
 	    error (SORT_FAILURE, 0, _("multiple compress programs specified"));
 	  compress_program = optarg;
 	  break;