/*
 * Copyright (c) 1980, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * @(#) Copyright (c) 1980, 1993 The Regents of the University of California.  All rights reserved.
 * @(#)main.c   8.1 (Berkeley) 6/6/93
 * $FreeBSD: src/usr.sbin/config/main.c,v 1.37.2.3 2001/06/13 00:25:53 cg Exp $
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <ctype.h>
#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <dirent.h>
#include <sysexits.h>
#include <unistd.h>
#include "y.tab.h"
#include "config.h"

#ifndef TRUE
#define TRUE    (1)
#endif

#ifndef FALSE
#define FALSE   (0)
#endif

#define CDIR    "../compile/"

char *  platformname;
char *  machinename;
char *  machinearchname;

struct cputype  *cputype;
struct opt      *opt, *mkopt;
struct opt_list *otab;

char *  PREFIX;
char    destdir[MAXPATHLEN];
char    srcdir[MAXPATHLEN - 32];

static int no_config_clobber = TRUE;
int     debugging;

extern int yyparse(void);
static void configfile(void);
static void get_srcdir(void);
static void usage(void);

/*
 * Config builds a set of files for building a UNIX
 * system given a description of the desired system.
 */
int
main(int argc, char *argv[])
{
        struct stat buf;
        int ch, len;
        char *p;
        char linkdest[MAXPATHLEN];
#if 0
        unsigned int i;
        char linksrc[64];
        static const char *emus[] = { "linux" };
#endif

        while ((ch = getopt(argc, argv, "d:gr")) != -1)
                switch (ch) {
                case 'd':
                        if (*destdir == '\0')
                                strlcpy(destdir, optarg, sizeof(destdir));
                        else
                                errx(2, "directory already set");
                        break;
                case 'g':
                        debugging++;
                        break;
                case 'r':
                        no_config_clobber = FALSE;
                        break;
                case '?':
                default:
                        usage();
                }
        argc -= optind;
        argv += optind;

        if (argc != 1)
                usage();

        if (freopen(PREFIX = *argv, "r", stdin) == NULL)
                err(2, "%s", PREFIX);

        if (*destdir != '\0') {
                len = strlen(destdir);
                while (len > 1 && destdir[len - 1] == '/')
                        destdir[--len] = '\0';
                get_srcdir();
        } else {
                strlcpy(destdir, CDIR, sizeof(destdir));
                strlcat(destdir, PREFIX, sizeof(destdir));
        }

        p = path(NULL);
        if (stat(p, &buf)) {
                if (mkdir(p, 0777))
                        err(2, "%s", p);
        }
        else if ((buf.st_mode & S_IFMT) != S_IFDIR) {
                errx(2, "%s isn't a directory", p);
        }
        else if (!no_config_clobber) {
                char tmp[strlen(p) + 8];

                fprintf(stderr, "Removing old directory %s:  ", p);
                fflush(stderr);
                snprintf(tmp, sizeof(tmp), "rm -rf %s", p);
                if (system(tmp)) {
                        fprintf(stderr, "Failed!\n");
                        err(2, "%s", tmp);
                }
                fprintf(stderr, "Done.\n");
                if (mkdir(p, 0777))
                        err(2, "%s", p);
        }

        dtab = NULL;
        if (yyparse())
                exit(3);
        if (platformname == NULL) {
                printf("Specify platform architecture, e.g. 'platform pc64'\n");
                exit(1);
        }
        if (machinename == NULL) {
                printf("Specify machine architecture, e.g. 'machine x86_64'\n");
                exit(1);
        }
        if (machinearchname == NULL) {
                printf("Specify cpu architecture, e.g. 'machine_arch x86_64'\n");
                exit(1);
        }
        newbus_ioconf();
        
        /*
         * "machine" points into platform/<PLATFORM>/include
         */
        if (*srcdir == '\0')
                snprintf(linkdest, sizeof(linkdest), "../../platform/%s/include",
                    platformname);
        else
                snprintf(linkdest, sizeof(linkdest), "%s/platform/%s/include",
                    srcdir, platformname);
        symlink(linkdest, path("machine"));

        /*
         * "machine_base" points into platform/<PLATFORM>
         */
        if (*srcdir == '\0')
                snprintf(linkdest, sizeof(linkdest), "../../platform/%s",
                    platformname);
        else
                snprintf(linkdest, sizeof(linkdest), "%s/platform/%s",
                    srcdir, platformname);
        symlink(linkdest, path("machine_base"));

        /*
         * "cpu" points to cpu/<MACHINE_ARCH>/include
         */
        if (*srcdir == '\0')
                snprintf(linkdest, sizeof(linkdest),
                         "../../cpu/%s/include", machinearchname);
        else
                snprintf(linkdest, sizeof(linkdest),
                         "%s/cpu/%s/include", srcdir, machinearchname);
        symlink(linkdest, path("cpu"));

        /*
         * "cpu_base" points to cpu/<MACHINE_ARCH>
         */
        if (*srcdir == '\0')
                snprintf(linkdest, sizeof(linkdest), "../../cpu/%s",
                    machinearchname);
        else
                snprintf(linkdest, sizeof(linkdest), "%s/cpu/%s",
                    srcdir, machinearchname);
        symlink(linkdest, path("cpu_base"));

        /*
         * XXX check directory structure for architecture subdirectories and
         * create the symlinks automatically XXX
         */
#if 0
        for (i = 0; i < NELEM(emus); ++i) {
                if (*srcdir == 0)  {
                        snprintf(linkdest, sizeof(linkdest),
                            "../../emulation/%s/%s",
                            emus[i], machinearchname);
                } else {
                        snprintf(linkdest, sizeof(linkdest),
                            "%s/emulation/%s/%s",
                            srcdir, emus[i], machinearchname);
                }
                snprintf(linksrc, sizeof(linksrc), "arch_%s", emus[i]);
                symlink(linkdest, path(linksrc));
        }
#endif

        options();                      /* make options .h files */
        makefile();                     /* build Makefile */
        headers();                      /* make a lot of .h files */
        configfile();                   /* put config file into kernel*/
        printf("Kernel build directory is %s\n", p);
        exit(EX_OK);
}

/*
 * get_srcdir
 *      determine the root of the kernel source tree
 *      and save that in srcdir.
 */
static void
get_srcdir(void)
{
        
        if (realpath("..", srcdir) == NULL)
                errx(2, "Unable to find root of source tree");
}

static void
usage(void)
{
        
        fprintf(stderr, "usage: config [-gpr] [-d destdir] sysname\n");
        exit(1);
}

/*
 * get_word
 *      returns EOF on end of file
 *      NULL on end of line
 *      pointer to the word otherwise
 */
char *
get_word(FILE *fp)
{
        static char line[80];
        int ch;
        char *cp;
        int escaped_nl = 0;

begin:
        while ((ch = getc(fp)) != EOF)
                if (ch != ' ' && ch != '\t')
                        break;
        if (ch == EOF)
                return((char *)EOF);
        if (ch == '\\') {
                escaped_nl = 1;
                goto begin;
        }
        if (ch == '\n') {
                if (escaped_nl) {
                        escaped_nl = 0;
                        goto begin;
                }
                else
                        return(NULL);
        }
        cp = line;
        *cp++ = ch;
        while ((ch = getc(fp)) != EOF) {
                if (isspace(ch))
                        break;
                *cp++ = ch;
        }
        *cp = 0;
        if (ch == EOF)
                return((char *)EOF);
        ungetc(ch, fp);
        return(line);
}

/*
 * get_quoted_word
 *      like get_word but will accept something in double or single quotes
 *      (to allow embedded spaces).
 */
char *
get_quoted_word(FILE *fp)
{
        static char line[256];
        int ch;
        char *cp;
        int escaped_nl = 0;

begin:
        while ((ch = getc(fp)) != EOF)
                if (ch != ' ' && ch != '\t')
                        break;
        if (ch == EOF)
                return((char *)EOF);
        if (ch == '\\') {
                escaped_nl = 1;
                goto begin;
        }
        if (ch == '\n') {
                if (escaped_nl) {
                        escaped_nl = 0;
                        goto begin;
                }
                else
                        return(NULL);
        }
        cp = line;
        if (ch == '"' || ch == '\'') {
                int quote = ch;

                while ((ch = getc(fp)) != EOF) {
                        if (ch == quote)
                                break;
                        if (ch == '\n') {
                                *cp = 0;
                                printf("config: missing quote reading `%s'\n",
                                        line);
                                exit(2);
                        }
                        *cp++ = ch;
                }
        } else {
                *cp++ = ch;
                while ((ch = getc(fp)) != EOF) {
                        if (isspace(ch))
                                break;
                        *cp++ = ch;
                }
                if (ch != EOF)
                        ungetc(ch, fp);
        }
        *cp = 0;
        if (ch == EOF)
                return((char *)EOF);
        return(line);
}

/*
 * prepend the path to a filename
 */
char *
path(const char *file)
{
        char *cp;

        cp = malloc((size_t)(strlen(destdir) + (file ? strlen(file) : 0) + 2));
        strcpy(cp, destdir);
        if (file != NULL) {
                strcat(cp, "/");
                strcat(cp, file);
        }
        return(cp);
}

static void
configfile(void)
{
        FILE *fi, *fo;
        char *p;
        int i;
        
        fi = fopen(PREFIX, "r");
        if (fi == NULL)
                err(2, "%s", PREFIX);
        fo = fopen(p = path("config.c.new"), "w");
        if (fo == NULL)
                err(2, "%s", p);
        fprintf(fo, "#include \"opt_config.h\"\n");
        fprintf(fo, "#ifdef INCLUDE_CONFIG_FILE \n");
        fprintf(fo, "/* Mark config as used, so gcc doesn't optimize it away. */\n");
        fprintf(fo, "#include <sys/types.h>\n");
        fprintf(fo, "__used\n");
        fprintf(fo, "static const char config[] = \"\\\n");
        fprintf(fo, "START CONFIG FILE %s\\n\\\n___", PREFIX);
        while (EOF != (i = getc(fi))) {
                if (i == '\n') {
                        fprintf(fo, "\\n\\\n___");
                } else if (i == '\"') {
                        fprintf(fo, "\\\"");
                } else if (i == '\\') {
                        fprintf(fo, "\\\\");
                } else {
                        putc(i, fo);
                }
        }
        fprintf(fo, "\\n\\\nEND CONFIG FILE %s\\n\\\n", PREFIX);
        fprintf(fo, "\";\n");
        fprintf(fo, "\n#endif /* INCLUDE_CONFIG_FILE */\n");
        fclose(fi);
        fclose(fo);
        moveifchanged(path("config.c.new"), path("config.c"));
}

/*
 * moveifchanged --
 *      compare two files; rename if changed.
 */
void
moveifchanged(const char *from_name, const char *to_name)
{
        char *p, *q;
        int changed;
        size_t tsize;
        struct stat from_sb, to_sb;
        int from_fd, to_fd;

        changed = 0;

        if ((from_fd = open(from_name, O_RDONLY)) < 0)
                err(EX_OSERR, "moveifchanged open(%s)", from_name);

        if ((to_fd = open(to_name, O_RDONLY)) < 0)
                changed++;

        if (!changed && fstat(from_fd, &from_sb) < 0)
                err(EX_OSERR, "moveifchanged fstat(%s)", from_name);

        if (!changed && fstat(to_fd, &to_sb) < 0)
                err(EX_OSERR, "moveifchanged fstat(%s)", to_name);

        if (!changed && from_sb.st_size != to_sb.st_size)
                changed++;

        tsize = (size_t)from_sb.st_size;

        if (!changed) {
                p = mmap(NULL, tsize, PROT_READ, MAP_SHARED, from_fd, (off_t)0);
#ifndef MAP_FAILED
#define MAP_FAILED ((caddr_t)-1)
#endif
                if (p == MAP_FAILED)
                        err(EX_OSERR, "mmap %s", from_name);
                q = mmap(NULL, tsize, PROT_READ, MAP_SHARED, to_fd, (off_t)0);
                if (q == MAP_FAILED)
                        err(EX_OSERR, "mmap %s", to_name);

                changed = memcmp(p, q, tsize);
                munmap(p, tsize);
                munmap(q, tsize);
        }
        if (changed) {
                if (rename(from_name, to_name) < 0)
                        err(EX_OSERR, "rename(%s, %s)", from_name, to_name);
        } else {
                if (unlink(from_name) < 0)
                        err(EX_OSERR, "unlink(%s)", from_name);
        }
}