From c6036b6f3dafa1e372ce57be3ef4b471533b04ca Mon Sep 17 00:00:00 2001
From: Ben Pfaff <blp@cs.stanford.edu>
Date: Sat, 8 Aug 2015 01:00:10 -0700
Subject: [PATCH] dump: Make it harder to get the usage wrong.

---
 dump.c | 157 +++++++++++++++++++++++++++++----------------------------
 1 file changed, 81 insertions(+), 76 deletions(-)

diff --git a/dump.c b/dump.c
index cba4509cd4..2c778210ff 100644
--- a/dump.c
+++ b/dump.c
@@ -878,90 +878,95 @@ main(int argc, char *argv[])
       exit(1);
     }
 
-  if (argc > 1)
+  if (argc != 2)
     {
-      if (!strcmp(argv[1], "title0"))
-        {
-          pos = 0x27;
-          if (match_byte (0x03)
-              || (match_byte (0x05) && match_byte (0x58)))
-            printf ("%s\n", get_string());
-          else
-            printf ("<unknown>\n");
-          return 0;
-        }
-      else if (!strcmp(argv[1], "title"))
-        {
-          dump_title();
-          exit(0);
-        }
-      else if (!strcmp(argv[1], "titleraw"))
-        {
-          const char fonts[] = "\x01\x31\x09\0\0\0SansSerif";
-          start = 0x27;
-          n = find(fonts, sizeof fonts - 1);
-        }
-      else if (!strcmp(argv[1], "fonts"))
-        {
-          const char fonts[] = "\x01\x31\x09\0\0\0SansSerif";
-          const char styles[] = "\xf0\0\0\0";
-          start = find(fonts, sizeof fonts - 1);
-          n = find(styles, sizeof styles - 1);
-        }
-      else if (!strcmp(argv[1], "styles"))
-        {
-          const char styles[] = "\xf0\0\0\0";
-          const char dimensions[] = "-,,,.\0";
-          start = find(styles, sizeof styles - 1);
-          n = find(dimensions, sizeof dimensions - 1) + sizeof dimensions - 1;
-        }
-      else if (!strcmp(argv[1], "dimensions") || !strcmp(argv[1], "all"))
-        {
-          pos = 0;
-          match_byte_assert(1);
-          match_byte_assert(0);
-
-          /* This might be a version number of some kind, because value 1 seems
-             to only appear in an SPV file that also required its own weird
-             special cases in dump_value_31(). */
-          version = get_u32();
-          pos -= 4;
-          if (!match_u32(1))
-            match_u32_assert(3);
+      fprintf (stderr, "usage: %s TYPE < .bin", argv[0]);
+      exit (1);
+    }
 
-          match_byte_assert(1);
-          if (!match_byte(0))
-            match_byte_assert(1);
-          match_byte_assert(0);
-          match_byte_assert(0);
-          if (!match_byte(0))
-            match_byte_assert(1);
-          pos++;
-          match_byte_assert(0);
-          match_byte_assert(0);
-          match_byte_assert(0);
-          dump_title ();
-          dump_fonts();
-          dump_dims ();
-          dump_data ();
-          match_byte (1);
-          if (pos != n)
-            {
-              fprintf (stderr, "%x / %x\n", pos, n);
-              exit(1);
-            }
-          exit(0);
-        }
+  if (!strcmp(argv[1], "title0"))
+    {
+      pos = 0x27;
+      if (match_byte (0x03)
+          || (match_byte (0x05) && match_byte (0x58)))
+        printf ("%s\n", get_string());
       else
+        printf ("<unknown>\n");
+      return 0;
+    }
+  else if (!strcmp(argv[1], "title"))
+    {
+      dump_title();
+      exit(0);
+    }
+  else if (!strcmp(argv[1], "titleraw"))
+    {
+      const char fonts[] = "\x01\x31\x09\0\0\0SansSerif";
+      start = 0x27;
+      n = find(fonts, sizeof fonts - 1);
+    }
+  else if (!strcmp(argv[1], "fonts"))
+    {
+      const char fonts[] = "\x01\x31\x09\0\0\0SansSerif";
+      const char styles[] = "\xf0\0\0\0";
+      start = find(fonts, sizeof fonts - 1);
+      n = find(styles, sizeof styles - 1);
+    }
+  else if (!strcmp(argv[1], "styles"))
+    {
+      const char styles[] = "\xf0\0\0\0";
+      const char dimensions[] = "-,,,.\0";
+      start = find(styles, sizeof styles - 1);
+      n = find(dimensions, sizeof dimensions - 1) + sizeof dimensions - 1;
+    }
+  else if (!strcmp(argv[1], "dimensions") || !strcmp(argv[1], "all"))
+    {
+      pos = 0;
+      match_byte_assert(1);
+      match_byte_assert(0);
+
+      /* This might be a version number of some kind, because value 1 seems
+         to only appear in an SPV file that also required its own weird
+         special cases in dump_value_31(). */
+      version = get_u32();
+      pos -= 4;
+      if (!match_u32(1))
+        match_u32_assert(3);
+
+      match_byte_assert(1);
+      if (!match_byte(0))
+        match_byte_assert(1);
+      match_byte_assert(0);
+      match_byte_assert(0);
+      if (!match_byte(0))
+        match_byte_assert(1);
+      pos++;
+      match_byte_assert(0);
+      match_byte_assert(0);
+      match_byte_assert(0);
+      dump_title ();
+      dump_fonts();
+      dump_dims ();
+      dump_data ();
+      match_byte (1);
+      if (pos != n)
         {
-          fprintf (stderr, "unknown section %s\n", argv[1]);
+          fprintf (stderr, "%x / %x\n", pos, n);
           exit(1);
         }
+      exit(0);
     }
-  else
-    start = 0x27;
+  else if (!strcmp(argv[1], "raw"))
+    {
+      start = 0x27;
 
-  dump_raw(stdout, start, n);
+      dump_raw(stdout, start, n);
+    }
+  else
+    {
+      fprintf (stderr, "unknown section %s\n", argv[1]);
+      exit(1);
+    }
 
   return 0;
 }
-- 
2.30.2