/* Copyright (C) 1994, Klaus Preschern.                        */
/* All rights reserved.                                        */
/* See the file COPYRIGHT.KP for a full description.           */

#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <string.h>
#include <sys/stat.h>

#define DEBUG			0
#define PATH_LEN		1024
#define QUAKE_LEN		1024
#define UNIT_LEN		1024

static char quake []
	= "/ex32/usr/local/bin/quake";
static char template_dir [PATH_LEN]
	= "/ex32/usr/local/lib/m3/pkg/m3build/templates";

static char template [PATH_LEN]		= "DOS";
static char build_dir [PATH_LEN]	= "DOS";
static char start_dir [PATH_LEN]	= ".";
static char quake_args [QUAKE_LEN]	= "";
static char units [UNIT_LEN]		= "";
static char show_hidden [12]		= "";
static char verbose [2]			= "n";
static char base [PATH_LEN]		= "";
static char parent [PATH_LEN]		= "";
static char tmp [PATH_LEN]		= "";
static char basetmp [PATH_LEN]		= "";
static char package_dir [PATH_LEN]	= "";
static char package [PATH_LEN]		= "";
static char query [PATH_LEN]		= "/ex32/tmp/m3find.$$";
static char unit [PATH_LEN]		= "";

static int is_dir (char * name)
  {
    struct stat statbuf;
    
    #if DEBUG
      printf ("is_dir (%s)\n", name);
    #endif
    if (stat (name, &statbuf) < 0) {
      return 0;
    }
    return (statbuf.st_mode & __S_IFDIR);
  }

static int readable (char * name)
  {
    /* we do not check for readability, just for existence */
    struct stat statbuf;
    #if DEBUG
      printf ("readable (%s)\n", name);
    #endif
    return (!(stat (name, &statbuf) < 0));
  }

static char * dircat (char * dir1, char * dir2)
  {
    char tmp1 [PATH_LEN], tmp2 [PATH_LEN];
    /* 'dir1' or 'dir2' could be 'tmp' */
    strcpy (tmp1, dir1);
    strcpy (tmp2, dir2);
    strcat (tmp1, "/");
    strcpy (tmp, tmp1);
    strcat (tmp, tmp2);
    #if DEBUG
      printf ("dircat (%s)\n", tmp);
    #endif
    return tmp;
  }

static int skip_blanks (char * name, int i)
  {
    while ((name [i] == ' ') && (name [i] != '\0')) {
      i++;
    }
    return i;
  }

static int getnext (char * part, char * components, int i)
  {
    int j = 0;
    i = skip_blanks (components, i);
    if (components [i] == '\0') {
      return -1;
    }
    while ((components [i] != ' ') && (components [i] != '\0')) {
      part [j++] = components [i++];
      part [j] = '\0';
    }
    return i;
  }

static void print_usage (void)
  {
    printf ("usage: m3where [options] [units]\n");
    printf ("-b <build_dir>       build with this template and in this directory (default=\'%s\')\n", build_dir);
    printf ("-T <template_dir>    use templates in specified directory (default=\'%s\')\n", template_dir);
    printf ("-d <start_dir>       start in this directory (default=\'%s\')\n", start_dir);
    printf ("-v                   verbose\n");
    printf ("-h                   show hidden\n");
    printf ("-<quake argument>    pass this argument to quake\n");
    printf ("<unit> ...         call quake with each unit\n");
    printf ("\n");
  }

/*
 * parse the command line
 */
 
static void parse_command_line (int argc, char ** argv)
  {
    int i = 1;
    while (i < argc) {
      if (strcmp (argv [i], "-b") == 0) {
  	/* -b) shift ; build_dir="$1" ; template="$1" ;; */
	if (i++ >= argc) break;
	strcpy (build_dir, argv [i]);
	strcpy (template, argv [i]);
      } else if (strcmp (argv [i], "-T") == 0) {
  	/* -T) shift ; template_dir="$1" ;; */
        if (i++ >= argc) break;
	strcpy (template_dir, argv [i]);
      } else if (strcmp (argv [i], "-d") == 0) {
  	/* -d) shift ; start_dir="$1" ;; */
	if (i++ >= argc) break;
	strcpy (start_dir, argv [i]);      
      } else if (strcmp (argv [i], "-v") == 0) {
  	/* -v) verbose="y" ;; */
        strcpy (verbose, "y");
      } else if (strcmp (argv [i], "-h") == 0) {
  	/* -h) show_hidden="show_hidden" ;; */
        strcpy (show_hidden, "show_hidden");
      } else if (argv [i] [0] == '-') {		/* quake args */
  	/* -*) quake_args="$quake_args $1" ;; */
        strcat (quake_args, " ");
	strcat (quake_args, argv [i]);
      } else {					/* units */
  	/* *)  units="$units $1" ;; */
        strcat (units, " ");
	strcat (units, argv [i]);
      }
      i++;
    }
    #if DEBUG
      printf (" --------------------------- \n");
      for (i = 0; i < argc; i++) {
        printf ("argv [%d] = %s\n", i, argv [i]);
      }
      printf (" --------------------------- \n");
    #endif
  }

/*
 * get basename
 */

static char * basename (char * name)
  {
    int i, len;
    i = len = strlen (name);
    while ((--i >= 0) && (name [i] != '/') && (name [i] != '\\')) ;
    /* i could be (-1) */
    strncpy (basetmp, &name [i+1], len - i + 1);
    #if DEBUG
      printf ("basename (%s) = %s\n", name, basetmp);
    #endif
    return basetmp;
  }
 
/*
 * get to the initial directory
 */

static void goto_initial_directory (void)
  {

    chdir (start_dir);    		/* cd "$start_dir" */
    getcwd (start_dir, PATH_LEN);    	/* start_dir=`pwd` */
    strcpy (base, basename (start_dir));/* base=`basename "$start_dir"` */
    chdir ("..");
    getcwd (parent, PATH_LEN);		/* parent=`cd .. ; pwd` */
    chdir (start_dir);
    #if DEBUG
      printf ("start_dir = %s, parent = %s, base = %s\n",
      start_dir, parent, base);
    #endif
  }

/*
 * move to the directory with derived objects
 */
static void goto_dir_with_derived_objects (void)
  {
    if (strcmp (base, build_dir) == 0) { /* if [ $base = $build_dir ] */
      strcpy (package_dir, parent);		/* package_dir=$parent */
    } else if (is_dir (build_dir)) {	/* elif [ -d "$build_dir" ] */
      strcpy (package_dir, start_dir);	/* package_dir="$start_dir" */
      printf ("--- cd %s ---\n", build_dir);
      chdir (build_dir);		/* cd "$build_dir" */
    } else if (is_dir (dircat ("..", build_dir))) {
      /* elif [ -d "../$build_dir" ] */
      /* we're in a sibling directory (probably "src") */
      strcpy (package_dir, parent);	/* set package_dir=$parent */
      chdir (dircat ("..", build_dir));	/* cd "../$build_dir" */
    } else {
        /* echo "m3where: cannot locate build directory $build_dir" */
      printf ("m3where: cannot locate build directory %s\n", build_dir);
      exit (-1);
    }
    /* package=`basename "$package_dir"` */
    strcpy (package, basename (package_dir));
    #if DEBUG
      printf ("package_dir = %s, build_dir = %s, package = %s\n",
               package_dir, build_dir, package);
    #endif
  }

/*
 * find a .M3EXPORTS file
 */
static void check_for_exportsfile (void)
  { 
    if (! readable (".M3EXPORTS")) {	/* if [ ! -r ".M3EXPORTS" ] */
      getcwd (tmp, PATH_LEN);
      /* echo "m3where: missing .M3EXPORTS file in `pwd`" */
      printf ("m3where: missing .M3EXPORTS file in %s\n", tmp);
      exit (-1);
    }
  }

/*
 * build the query
 */
static void build_query (int argc, char ** argv)
  {
    FILE * fd; int i;
    /* query="/tmp/m3find.$$" - see query init */
    if ((fd = fopen (query, "w")) == NULL) {
      printf ("m3where: cannot create %s\n", query);
      exit (-1);
    }
    /* echo "% m3where $*" >$query */
    fprintf (fd, "%% ");
    for (i = 0; i < argc; i++) {
      fprintf (fd, "%s ", argv [i]);
    }
    fprintf (fd, "\n");
    
    if (strlen (units) == 0) {		/* if [ "x$units" = "x" ] */
      /* echo "enum_units(\"$show_hidden\")" >>$query */
      fprintf (fd, "enum_units (\"%s\")\n", show_hidden);
    } else {
      i = 0;
      while ((i = getnext (unit, units, i)) > 0) {   /* for u in $units */
        /* echo "find_unit($u, \"$show_hidden\")" >>$query */
        fprintf (fd, "find_unit (%s, \"%s\")\n", unit, show_hidden);
      }
    }
    fclose (fd);
  }

extern char ** environ;

static int execute (char * quake, char * package_dir,
		    char * package, char * build_dir, char * template_dir,
		    char * quake_args, char * exports, char * query)
  {
      /* quake -DPACKAGE_DIR=$package_dir -DPACKAGE=$package
       * -DBUILD_DIR=$build_dir $template_dir/$template $quake_args
       * .M3EXPORTS query
       */
       
     char args [30] [PATH_LEN]; int i = 0, j = 0, status;
     char quake_arg [PATH_LEN]; char * argv [30];
     
     strcpy (args [0], quake);
     argv [0] = &args [0][0];

     strcpy (args [1], "-DPACKAGE_DIR=");
     strcat (args [1], package_dir);
     argv [1] = &args [1][0];
     
     strcpy (args [2], "-DPACKAGE=");
     strcat (args [2], package);
     argv [2] = &args [2][0];
     
     strcpy (args [3], "-DBUILD_DIR=");
     strcat (args [3], build_dir);
     argv [3] = &args [3][0];
     
     strcpy (args [4], template_dir);
     argv [4] = &args [4][0];

     while ((i = getnext (quake_arg, quake_args, i)) > 0) {
       strcpy (args [5 + j], quake_arg);
       argv [5 + j] = &args [5 + j][0];
       j++;
     }   
       
     strcpy (args [5 + j], exports);
     argv [5 + j] = &args [5 + j][0];
     j++;
     
     strcpy (args [5 + j], query);
     argv [5 + j] = &args [5 + j][0];
     argv [5 + j + 1] = 0;
     
     #if DEBUG
     j = 0;
     printf ("-----------------------------\n");
     while (argv [j]) {
       printf ("argv [%d] = %s\n", j, argv [j]);
       j++;
     }
     printf ("-----------------------------\n");
     #endif

     if (vfork () == 0) {
       /* child */
       if (execve (quake, argv, environ) < 0) {
         printf ("m3where: cannot execute %s\n", quake);
	 exit (-1);
       }
     }
     /* parent */
     wait (&status);     
     return status;
  }

/*
 * prepare for the worst...
 *
 * trap 'rm -f $query ; exit 1' 1 2 3 15
 */
 
/*
 * evaulate the query
 */
static void evaluate_query (void)
  {
    if (strcmp (verbose, "y") == 0) {	/* if [ x"$verbose" = xy ] */
      /* echo "$quake -DPACKAGE_DIR=$package_dir -DPACKAGE=$package
       * -DBUILD_DIR=$build_dir $template_dir/$template $quake_args
       * .M3EXPORTS $query"
       */
      printf ("%s -DPACKAGE_DIR=%s -DPACKAGE=%s ",
              quake, package_dir, package);
	printf ("-DBUILD_DIR=%s %s/%s %s .M3EXPORTS %s\n", 
            build_dir, template_dir, template, quake_args, query);
    }
    /* $quake -DPACKAGE_DIR=$package_dir -DPACKAGE=$package
     * -DBUILD_DIR=$build_dir $template_dir/$template $quake_args
     * .M3EXPORTS $query
     */ 
    if (execute (quake, package_dir, package, build_dir,
            dircat (template_dir, template), quake_args, 
	    ".M3EXPORTS", query) < 0) {
	unlink (query);		/* rm -f $query */
        exit (-1);
    }
    unlink (query);		/* rm -f $query */
  }
  
int main (int argc, char ** argv, char ** envp)
  {
    parse_command_line (argc, argv);
    goto_initial_directory ();
    goto_dir_with_derived_objects ();
    check_for_exportsfile ();
    build_query (argc, argv);    
    evaluate_query ();
    return 0;
  }