Mesa (master): glsl: Improve usage message for glsl_compiler

[Kenneth Graunke]

Module: Mesa
Branch: master
Commit: 7819435f2ef484696560547fbc1325cb97c7174b
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=7819435f2ef484696560547fbc1325cb97c7174b

Author: Chad Versace <chad.versace at intel.com>
Date:   Wed Nov 17 15:28:36 2010 -0800

glsl: Improve usage message for glsl_compiler

The new usage message lists possible command line options. (Newcomers to Mesa
currently have to trawl through the source to find the command line options,
and we should save them from that trouble.)

Example Output
--------------
usage: ./glsl_compiler [options] <file.vert | file.geom | file.frag>

Possible options are:
    --glsl-es
    --dump-ast
    --dump-hir
    --dump-lir
    --link

---

 src/glsl/main.cpp |   28 +++++++++++++++++++---------
 1 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/src/glsl/main.cpp b/src/glsl/main.cpp
index 08a44c9..3302851 100644
--- a/src/glsl/main.cpp
+++ b/src/glsl/main.cpp
@@ -146,15 +146,6 @@ load_text_file(void *ctx, const char *file_name)
 	return text;
 }
 
-
-void
-usage_fail(const char *name)
-{
-      printf("%s <filename.frag|filename.vert>\n", name);
-      exit(EXIT_FAILURE);
-}
-
-
 int glsl_es = 0;
 int dump_ast = 0;
 int dump_hir = 0;
@@ -170,6 +161,25 @@ const struct option compiler_opts[] = {
    { NULL, 0, NULL, 0 }
 };
 
+/**
+ * \brief Print proper usage and exit with failure.
+ */
+void
+usage_fail(const char *name)
+{
+
+   const char *header =
+      "usage: %s [options] <file.vert | file.geom | file.frag>\n"
+      "\n"
+      "Possible options are:\n";
+   printf(header, name, name);
+   for (const struct option *o = compiler_opts; o->name != 0; ++o) {
+      printf("    --%s\n", o->name);
+   }
+   exit(EXIT_FAILURE);
+}
+
+
 void
 compile_shader(struct gl_context *ctx, struct gl_shader *shader)
 {