Boost Jam code cleanup - extracted running command counting out of platform specific exec*.c modules and moved it to the central make1.c module. Simplified upper running command count checking since with the new '-j' command-line parameter and the PARALLELISM built-in variable value checking we now know that globs.jobs is always in the [1, MAXJOBS] range.

[SVN r79075]

src/engine/execcmd.h

@@ -52,7 +52,7 @@ void exec_cmd
     char const * target
 );
 
-int exec_wait();
+void exec_wait();
 
 
 /******************************************************************************

src/engine/execnt.c

@@ -113,7 +113,6 @@ static void reportWindowsError( char const * const apiName );
 #define MAX_RAW_COMMAND_LENGTH 32766
 
 static int intr_installed;
-static int cmdsrunning;
 
 
 /* The list of commands we run. */
@@ -304,20 +303,11 @@ void exec_cmd
         exit( EXITBAD );
     }
 
-    ++cmdsrunning;
-
     /* Invoke the actual external process using the constructed command line. */
     invoke_cmd( cmd_local->value, slot );
 
     /* Free our local command string copy. */
     string_free( cmd_local );
-
-    /* Wait until we are under the limit of concurrent commands. Do not trust
-     * globs.jobs alone.
-     */
-    while ( ( cmdsrunning >= MAXJOBS ) || ( cmdsrunning >= globs.jobs ) )
-        if ( !exec_wait() )
-            break;
 }
 
 
@@ -326,19 +316,12 @@ void exec_cmd
  *  * wait and drive at most one execution completion.
  *  * waits for one command to complete, while processing the i/o for all
  *    ongoing commands.
- *
- *   Returns 0 if called when there were no more commands being executed or 1
- * otherwise.
  */
 
-int exec_wait()
+void exec_wait()
 {
     int i = -1;
 
-    /* Handle naive make1() which does not know if cmds are running. */
-    if ( !cmdsrunning )
-        return 0;
-
     /* Wait for a command to complete, while snarfing up any output. */
     do
     {
@@ -354,7 +337,6 @@ int exec_wait()
     while ( i < 0 );
 
     /* We have a command... process it. */
-    --cmdsrunning;
     {
         timing_info time;
         int rstat;
@@ -409,8 +391,6 @@ int exec_wait()
         cmdtab[ i ].exit_code = 0;
         cmdtab[ i ].exit_reason = EXIT_OK;
     }
-
-    return 1;
 }
 
 

src/engine/execunix.c

@@ -64,7 +64,6 @@ static int get_free_cmdtab_slot();
 
 static clock_t tps;
 static int select_timeout;
-static int cmdsrunning;
 static int old_time_initialized;
 static struct tms old_time;
 
@@ -149,9 +148,6 @@ void exec_cmd
             printf( "    argv[%d] = '%s'\n", i, argv[ i ] );
     }
 
-    /* Increment jobs running. */
-    ++cmdsrunning;
-
     /* Save off actual command string. */
     cmdtab[ slot ].command = BJAM_MALLOC_ATOMIC( command->size + 1 );
     strcpy( cmdtab[ slot ].command, command->value );
@@ -301,13 +297,6 @@ void exec_cmd
         cmdtab[ slot ].action_length = 0;
         cmdtab[ slot ].target_length = 0;
     }
-
-    /* Wait until we are under the limit of concurrent commands. Do not trust
-     * globs.jobs alone.
-     */
-    while ( ( cmdsrunning >= MAXJOBS ) || ( cmdsrunning >= globs.jobs ) )
-        if ( !exec_wait() )
-            break;
 }
 
 #undef EXECCMD_PIPE_READ
@@ -432,18 +421,14 @@ void populate_file_descriptors( int * const fmax, fd_set * const fds )
  * at least one has been registered.
  */
 
-int exec_wait()
+void exec_wait()
 {
     int fd_max;
     int finished = 0;
     fd_set fds;
 
-    /* Handle naive make1() which does not know if commands are running. */
-    if ( !cmdsrunning )
-        return 0;
-
     /* Process children that signaled. */
-    while ( !finished && cmdsrunning )
+    while ( !finished )
     {
         int i;
         int ret;
@@ -525,8 +510,6 @@ int exec_wait()
                 old_time = new_time;
 
                 /* Drive the completion. */
-                --cmdsrunning;
-
                 if ( interrupted() )
                     rstat = EXEC_CMD_INTR;
                 else if ( status )
@@ -558,8 +541,6 @@ int exec_wait()
             }
         }
     }
-
-    return 1;
 }
 
 

src/engine/make1.c

@@ -111,6 +111,9 @@ static stack state_stack = { NULL };
 
 static state * state_freelist = NULL;
 
+/* Currently running command counter. */
+static int cmdsrunning;
+
 
 static state * alloc_state()
 {
@@ -204,7 +207,7 @@ int make1( TARGET * t )
     /* Recursively make the target and its dependencies. */
     push_state( &state_stack, t, NULL, T_STATE_MAKE1A );
 
-    do
+    while ( 1 )
     {
         while ( ( pState = current_state( &state_stack ) ) )
         {
@@ -222,9 +225,11 @@ int make1( TARGET * t )
                     assert( !"make1(): Invalid state detected." );
             }
         }
+        if ( !cmdsrunning )
+            break;
+        /* Wait for outstanding commands to finish running. */
+        exec_wait();
     }
-    /* Wait for any outstanding commands to finish running. */
-    while ( exec_wait() );
 
     clear_state_freelist();
 
@@ -538,10 +543,21 @@ static void make1c( state * pState )
         }
         else
         {
-            /* Pop state first because exec_cmd() could push state. */
+            /* Pop state first because exec_wait() will push state. */
             pop_state( &state_stack );
+
+            /* Execute the actual build command. */
             exec_cmd( cmd->buf, make_closure, pState->t, cmd->shell, rule_name,
                 target_name );
+
+            /* Increment the jobs running counter. */
+            ++cmdsrunning;
+
+            /* Wait until we are under the concurrent command count limit. */
+            assert( 0 < globs.jobs );
+            assert( globs.jobs <= MAXJOBS );
+            while ( cmdsrunning >= globs.jobs )
+                exec_wait();
         }
     }
     else
@@ -814,6 +830,8 @@ static void make_closure
 {
     TARGET * built = (TARGET *)closure;
 
+    --cmdsrunning;
+
     call_timing_rule( built, time );
     if ( DEBUG_EXECCMD )
         printf( "%f sec system; %f sec user\n", time->system, time->user );