Make MFLAGS and MAKEFLAGS more reliable and predictable.

Ensure all simple flags are kept in the initial batch of flags.
Do not allow any flags with options in that batch.
If there are only non-simple flags ensure MAKEFLAGS begins with " ".
Don't let MFLAGS start with "- ".

1 files changed, 80 insertions, 115 deletions

diff --git a/main.c b/main.c
index 4588da5..6a956ad 100644
--- a/main.c
+++ b/main.c
@@ -385,42 +385,26 @@ static const char *const usage[] =
     NULL
   };
 
-/* The table of command switches.  */
+/* The table of command switches.
+   Order matters here: this is the order MAKEFLAGS will be constructed.
+   So be sure all simple flags (single char, no argument) come first.  */
 
 static const struct command_switch switches[] =
   {
     { 'b', ignore, 0, 0, 0, 0, 0, 0, 0 },
     { 'B', flag, &always_make_set, 1, 1, 0, 0, 0, "always-make" },
-    { 'C', filename, &directories, 0, 0, 0, 0, 0, "directory" },
     { 'd', flag, &debug_flag, 1, 1, 0, 0, 0, 0 },
-    { CHAR_MAX+1, string, &db_flags, 1, 1, 0, "basic", 0, "debug" },
 #ifdef WINDOWS32
     { 'D', flag, &suspend_flag, 1, 1, 0, 0, 0, "suspend-for-debug" },
 #endif
     { 'e', flag, &env_overrides, 1, 1, 0, 0, 0, "environment-overrides", },
-    { 'f', filename, &makefiles, 0, 0, 0, 0, 0, "file" },
     { 'h', flag, &print_usage_flag, 0, 0, 0, 0, 0, "help" },
     { 'i', flag, &ignore_errors_flag, 1, 1, 0, 0, 0, "ignore-errors" },
-    { 'I', filename, &include_directories, 1, 1, 0, 0, 0,
-      "include-dir" },
-    { 'j', positive_int, &job_slots, 1, 1, 0, &inf_jobs, &default_job_slots,
-      "jobs" },
-    { CHAR_MAX+2, string, &jobserver_fds, 1, 1, 0, 0, 0, "jobserver-fds" },
     { 'k', flag, &keep_going_flag, 1, 1, 0, 0, &default_keep_going_flag,
       "keep-going" },
-#ifndef NO_FLOAT
-    { 'l', floating, &max_load_average, 1, 1, 0, &default_load_average,
-      &default_load_average, "load-average" },
-#else
-    { 'l', positive_int, &max_load_average, 1, 1, 0, &default_load_average,
-      &default_load_average, "load-average" },
-#endif
     { 'L', flag, &check_symlink_flag, 1, 1, 0, 0, 0, "check-symlink-times" },
     { 'm', ignore, 0, 0, 0, 0, 0, 0, 0 },
     { 'n', flag, &just_print_flag, 1, 1, 1, 0, 0, "just-print" },
-    { 'o', filename, &old_files, 0, 0, 0, 0, 0, "old-file" },
-    { 'O', string, &output_sync_option, 1, 1, 0, "target", 0, "output-sync" },
-    { CHAR_MAX+7, string, &sync_mutex, 1, 1, 0, 0, 0, "sync-mutex" },
     { 'p', flag, &print_data_base_flag, 1, 1, 0, 0, 0, "print-data-base" },
     { 'q', flag, &question_flag, 1, 1, 1, 0, 0, "question" },
     { 'r', flag, &no_builtin_rules_flag, 1, 1, 0, 0, 0, "no-builtin-rules" },
@@ -430,15 +414,37 @@ static const struct command_switch switches[] =
     { 'S', flag_off, &keep_going_flag, 1, 1, 0, 0, &default_keep_going_flag,
       "no-keep-going" },
     { 't', flag, &touch_flag, 1, 1, 1, 0, 0, "touch" },
-    { CHAR_MAX+3, string, &trace_option, 1, 1, 0, "rule", 0, "trace" },
     { 'v', flag, &print_version_flag, 1, 1, 0, 0, 0, "version" },
     { 'w', flag, &print_directory_flag, 1, 1, 0, 0, 0, "print-directory" },
+
+    /* These options take arguments.  */
+    { 'C', filename, &directories, 0, 0, 0, 0, 0, "directory" },
+    { 'f', filename, &makefiles, 0, 0, 0, 0, 0, "file" },
+    { 'I', filename, &include_directories, 1, 1, 0, 0, 0,
+      "include-dir" },
+    { 'j', positive_int, &job_slots, 1, 1, 0, &inf_jobs, &default_job_slots,
+      "jobs" },
+#ifndef NO_FLOAT
+    { 'l', floating, &max_load_average, 1, 1, 0, &default_load_average,
+      &default_load_average, "load-average" },
+#else
+    { 'l', positive_int, &max_load_average, 1, 1, 0, &default_load_average,
+      &default_load_average, "load-average" },
+#endif
+    { 'o', filename, &old_files, 0, 0, 0, 0, 0, "old-file" },
+    { 'O', string, &output_sync_option, 1, 1, 0, "target", 0, "output-sync" },
+    { 'W', filename, &new_files, 0, 0, 0, 0, 0, "what-if" },
+
+    /* These are long-style options.  */
+    { CHAR_MAX+1, string, &db_flags, 1, 1, 0, "basic", 0, "debug" },
+    { CHAR_MAX+2, string, &jobserver_fds, 1, 1, 0, 0, 0, "jobserver-fds" },
+    { CHAR_MAX+3, string, &trace_option, 1, 1, 0, "rule", 0, "trace" },
     { CHAR_MAX+4, flag, &inhibit_print_directory_flag, 1, 1, 0, 0, 0,
       "no-print-directory" },
-    { 'W', filename, &new_files, 0, 0, 0, 0, 0, "what-if" },
     { CHAR_MAX+5, flag, &warn_undefined_variables_flag, 1, 1, 0, 0, 0,
       "warn-undefined-variables" },
     { CHAR_MAX+6, string, &eval_strings, 1, 0, 0, 0, 0, "eval" },
+    { CHAR_MAX+7, string, &sync_mutex, 1, 1, 0, 0, 0, "sync-mutex" },
     { 0, 0, 0, 0, 0, 0, 0, 0, 0 }
   };
 
@@ -2942,7 +2948,6 @@ define_makeflags (int all, int makefile)
   const struct command_switch *cs;
   char *flagstring;
   register char *p;
-  unsigned int words;
   struct variable *v;
 
   /* We will construct a linked list of 'struct flag's describing
@@ -2957,18 +2962,24 @@ define_makeflags (int all, int makefile)
       const char *arg;
     };
   struct flag *flags = 0;
+  struct flag *last = 0;
   unsigned int flagslen = 0;
 #define ADD_FLAG(ARG, LEN) \
   do {                                                                        \
     struct flag *new = alloca (sizeof (struct flag));                         \
     new->cs = cs;                                                             \
     new->arg = (ARG);                                                         \
-    new->next = flags;                                                        \
-    flags = new;                                                              \
+    new->next = 0;                                                            \
+    if (! flags)                                                              \
+      flags = new;                                                            \
+    else                                                                      \
+      last->next = new;                                                       \
+    last = new;                                                               \
     if (new->arg == 0)                                                        \
-      ++flagslen;               /* Just a single flag letter.  */             \
+      /* Just a single flag letter: " -x"  */                                 \
+      flagslen += 3;                                                          \
     else                                                                      \
-      /* " -xfoo", plus space to expand "foo".  */                            \
+      /* " -xfoo", plus space to escape "foo".  */                            \
       flagslen += 1 + 1 + 1 + (3 * (LEN));                                    \
     if (!short_option (cs->c))                                                \
       /* This switch has no single-letter version, so we use the long.  */    \
@@ -3039,11 +3050,8 @@ define_makeflags (int all, int makefile)
               struct stringlist *sl = *(struct stringlist **) cs->value_ptr;
               if (sl != 0)
                 {
-                  /* Add the elements in reverse order, because all the flags
-                     get reversed below; and the order matters for some
-                     switches (like -I).  */
-                  unsigned int i = sl->idx;
-                  while (i-- > 0)
+                  unsigned int i;
+                  for (i = 0; i < sl->idx; ++i)
                     ADD_FLAG (sl->list[i], strlen (sl->list[i]));
                 }
             }
@@ -3053,117 +3061,85 @@ define_makeflags (int all, int makefile)
           abort ();
         }
 
-  /* Four more for the possible " -- ".  */
-  flagslen += 4 + CSTRLEN (posixref) + 1 + CSTRLEN (evalref) + 1;
-
 #undef  ADD_FLAG
 
+  /* Four more for the possible " -- ", plus variable references.  */
+  flagslen += 4 + CSTRLEN (posixref) + 1 + CSTRLEN (evalref) + 1;
+
   /* Construct the value in FLAGSTRING.
      We allocate enough space for a preceding dash and trailing null.  */
   flagstring = alloca (1 + flagslen + 1);
   memset (flagstring, '\0', 1 + flagslen + 1);
   p = flagstring;
-  words = 1;
+
+  /* Start with a dash, for MFLAGS.  */
   *p++ = '-';
-  while (flags != 0)
+
+  /* Add simple options as a group.  */
+  while (flags != 0 && !flags->arg && short_option (flags->cs->c))
     {
+      *p++ = flags->cs->c;
+      flags = flags->next;
+    }
+
+  /* Now add more complex flags: ones with options and/or long names.  */
+  while (flags)
+    {
+      *p++ = ' ';
+      *p++ = '-';
+
       /* Add the flag letter or name to the string.  */
       if (short_option (flags->cs->c))
         *p++ = flags->cs->c;
       else
         {
-          /* If we don't have a dash, start a double-dash.  */
-          if (p[-1] != '-')
-            {
-              *p++ = ' ';
-              *p++ = '-';
-            }
+          /* Long options require a double-dash.  */
           *p++ = '-';
           strcpy (p, flags->cs->long_name);
           p += strlen (p);
         }
-      if (flags->arg != 0)
-        {
-          /* A flag that takes an optional argument which in this case is
-             omitted is specified by ARG being "".  We must distinguish
-             because a following flag appended without an intervening " -"
-             is considered the arg for the first.  */
-          if (flags->arg[0] != '\0')
-            {
-              /* Add its argument too.  Long options require '='.  */
-              if (!short_option (flags->cs->c))
-                *p++ = '=';
-              p = quote_for_env (p, flags->arg);
-            }
-          ++words;
-          /* Write a following space and dash, for the next flag.  */
-          *p++ = ' ';
-          *p++ = '-';
-        }
-      else if (!short_option (flags->cs->c))
+      /* An omitted optional argument has an ARG of "".  */
+      if (flags->arg && flags->arg[0] != '\0')
         {
-          ++words;
-          /* Long options must each go in their own word,
-             so we write the following space and dash.  */
-          *p++ = ' ';
-          *p++ = '-';
+          if (!short_option (flags->cs->c))
+            /* Long options require '='.  */
+            *p++ = '=';
+          p = quote_for_env (p, flags->arg);
         }
       flags = flags->next;
     }
 
-  /* Define MFLAGS before appending variable definitions.  */
-
+  /* If no flags at all, get rid of the initial dash.  */
   if (p == &flagstring[1])
-    /* No flags.  */
-    flagstring[0] = '\0';
-  else if (p[-1] == '-')
     {
-      /* Kill the final space and dash.  */
-      p -= 2;
-      *p = '\0';
+      flagstring[0] = '\0';
+      p = flagstring;
     }
-  else
-    /* Terminate the string.  */
-    *p = '\0';
 
-  /* Since MFLAGS is not parsed for flags, there is no reason to
+  /* Define MFLAGS before appending variable definitions.  Omit an initial
+     empty dash.  Since MFLAGS is not parsed for flags, there is no reason to
      override any makefile redefinition.  */
-  define_variable_cname ("MFLAGS", flagstring, o_env, 1);
+  define_variable_cname ("MFLAGS",
+                         flagstring + (flagstring[0] == '-' && flagstring[1] == ' ' ? 2 : 0),
+                         o_env, 1);
 
   /* Write a reference to -*-eval-flags-*-, which contains all the --eval
      flag options.  */
   if (eval_strings)
     {
-      if (p == &flagstring[1])
-        /* No flags written, so elide the leading dash already written.  */
-        p = flagstring;
-      else
-        *p++ = ' ';
+      *p++ = ' ';
       memcpy (p, evalref, CSTRLEN (evalref));
       p += CSTRLEN (evalref);
     }
 
   if (all && command_variables != 0)
     {
-      /* Now write a reference to $(MAKEOVERRIDES), which contains all the
-         command-line variable definitions.  */
+      /* Write a reference to $(MAKEOVERRIDES), which contains all the
+         command-line variable definitions.  Separate the variables from the
+         switches with a "--" arg.  */
 
-      if (p == &flagstring[1])
-        /* No flags written, so elide the leading dash already written.  */
-        p = flagstring;
-      else
-        {
-          /* Separate the variables from the switches with a "--" arg.  */
-          if (p[-1] != '-')
-            {
-              /* We did not already write a trailing " -".  */
-              *p++ = ' ';
-              *p++ = '-';
-            }
-          /* There is a trailing " -"; fill it out to " -- ".  */
-          *p++ = '-';
-          *p++ = ' ';
-        }
+      strcpy (p, " -- ");
+      p += 4;
 
       /* Copy in the string.  */
       if (posix_pedantic)
@@ -3177,20 +3153,9 @@ define_makeflags (int all, int makefile)
           p += CSTRLEN (ref);
         }
     }
-  else if (p == &flagstring[1])
-    {
-      words = 0;
-      --p;
-    }
-  else if (p[-1] == '-')
-    /* Kill the final space and dash.  */
-    p -= 2;
-  /* Terminate the string.  */
-  *p = '\0';
 
-  /* If there are switches, omit the leading dash unless it is a single long
-     option with two leading dashes.  */
-  if (flagstring[0] == '-' && flagstring[1] != '-')
+  /* If there is a leading dash, omit it.  */
+  if (flagstring[0] == '-')
     ++flagstring;
 
   /* This used to use o_env, but that lost when a makefile defined MAKEFLAGS.