/*
 * Copyright (c) 1992, Brian Berliner and Jeff Polk
 * Copyright (c) 1989-1992, Brian Berliner
 * 
 * You may distribute under the terms of the GNU General Public License as
 * specified in the README file that comes with the CVS 1.4 kit.
 * 
 * Patch
 * 
 * Create a Larry Wall format "patch" file between a previous release and the
 * current head of a module, or between two releases.  Can specify the
 * release as either a date or a revision number.
 */

#include "cvs.h"
#include "getline.h"

static RETSIGTYPE patch_cleanup PROTO((void));
static Dtype patch_dirproc PROTO((char *dir, char *repos, char *update_dir));
static int patch_fileproc PROTO((struct file_info *finfo));
static int patch_proc PROTO((int *pargc, char **argv, char *xwhere,
		       char *mwhere, char *mfile, int shorten,
		       int local_specified, char *mname, char *msg));

static int force_tag_match = 1;
static int patch_short = 0;
static int toptwo_diffs = 0;
static int local = 0;
static char *options = NULL;
static char *rev1 = NULL;
static int rev1_validated = 1;
static char *rev2 = NULL;
static int rev2_validated = 1;
static char *date1 = NULL;
static char *date2 = NULL;
static char tmpfile1[L_tmpnam+1], tmpfile2[L_tmpnam+1], tmpfile3[L_tmpnam+1];
static int unidiff = 0;

static const char *const patch_usage[] =
{
    "Usage: %s %s [-fl] [-c|-u] [-s|-t] [-V %%d]\n",
    "    -r rev|-D date [-r rev2 | -D date2] modules...\n",
    "\t-f\tForce a head revision match if tag/date not found.\n",
    "\t-l\tLocal directory only, not recursive\n",
    "\t-c\tContext diffs (default)\n",
    "\t-u\tUnidiff format.\n",
    "\t-s\tShort patch - one liner per file.\n",
    "\t-t\tTop two diffs - last change made to the file.\n",
    "\t-D date\tDate.\n",
    "\t-r rev\tRevision - symbolic or numeric.\n",
    "\t-V vers\tUse RCS Version \"vers\" for keyword expansion.\n",
    NULL
};

int
patch (argc, argv)
    int argc;
    char **argv;
{
    register int i;
    int c;
    int err = 0;
    DBM *db;

    if (argc == -1)
	usage (patch_usage);

    optind = 1;
    while ((c = getopt (argc, argv, "V:k:cuftsQqlRD:r:")) != -1)
    {
	switch (c)
	{
	    case 'Q':
	    case 'q':
#ifdef SERVER_SUPPORT
		/* The CVS 1.5 client sends these options (in addition to
		   Global_option requests), so we must ignore them.  */
		if (!server_active)
#endif
		    error (1, 0,
			   "-q or -Q must be specified before \"%s\"",
			   command_name);
		break;
	    case 'f':
		force_tag_match = 0;
		break;
	    case 'l':
		local = 1;
		break;
	    case 'R':
		local = 0;
		break;
	    case 't':
		toptwo_diffs = 1;
		break;
	    case 's':
		patch_short = 1;
		break;
	    case 'D':
		if (rev2 != NULL || date2 != NULL)
		    error (1, 0,
		       "no more than two revisions/dates can be specified");
		if (rev1 != NULL || date1 != NULL)
		    date2 = Make_Date (optarg);
		else
		    date1 = Make_Date (optarg);
		break;
	    case 'r':
		if (rev2 != NULL || date2 != NULL)
		    error (1, 0,
		       "no more than two revisions/dates can be specified");
		if (rev1 != NULL || date1 != NULL)
		    rev2 = optarg;
		else
		    rev1 = optarg;
		break;
	    case 'k':
		if (options)
		    free (options);
		options = RCS_check_kflag (optarg);
		break;
	    case 'V':
		if (atoi (optarg) <= 0)
		    error (1, 0, "must specify a version number to -V");
		if (options)
		    free (options);
		options = xmalloc (strlen (optarg) + 1 + 2);	/* for the -V */
		(void) sprintf (options, "-V%s", optarg);
		break;
	    case 'u':
		unidiff = 1;		/* Unidiff */
		break;
	    case 'c':			/* Context diff */
		unidiff = 0;
		break;
	    case '?':
	    default:
		usage (patch_usage);
		break;
	}
    }
    argc -= optind;
    argv += optind;

    /* Sanity checks */
    if (argc < 1)
	usage (patch_usage);

    if (toptwo_diffs && patch_short)
	error (1, 0, "-t and -s options are mutually exclusive");
    if (toptwo_diffs && (date1 != NULL || date2 != NULL ||
			 rev1 != NULL || rev2 != NULL))
	error (1, 0, "must not specify revisions/dates with -t option!");

    if (!toptwo_diffs && (date1 == NULL && date2 == NULL &&
			  rev1 == NULL && rev2 == NULL))
	error (1, 0, "must specify at least one revision/date!");
    if (date1 != NULL && date2 != NULL)
	if (RCS_datecmp (date1, date2) >= 0)
	    error (1, 0, "second date must come after first date!");

    /* if options is NULL, make it a NULL string */
    if (options == NULL)
	options = xstrdup ("");

#ifdef CLIENT_SUPPORT
    if (client_active)
    {
	/* We're the client side.  Fire up the remote server.  */
	start_server ();
	
	ign_setup ();

	if (local)
	    send_arg("-l");
	if (force_tag_match)
	    send_arg("-f");
	if (toptwo_diffs)
	    send_arg("-t");
	if (patch_short)
	    send_arg("-s");
	if (unidiff)
	    send_arg("-u");

	if (rev1)
	    option_with_arg ("-r", rev1);
	if (date1)
	    client_senddate (date1);
	if (rev2)
	    option_with_arg ("-r", rev2);
	if (date2)
	    client_senddate (date2);
	if (options[0] != '\0')
	    send_arg (options);

	{
	    int i;
	    for (i = 0; i < argc; ++i)
		send_arg (argv[i]);
	}

	send_to_server ("rdiff\012", 0);
        return get_responses_and_close ();
    }
#endif

    /* clean up if we get a signal */
#ifdef SIGHUP
    (void) SIG_register (SIGHUP, patch_cleanup);
#endif
#ifdef SIGINT
    (void) SIG_register (SIGINT, patch_cleanup);
#endif
#ifdef SIGQUIT
    (void) SIG_register (SIGQUIT, patch_cleanup);
#endif
#ifdef SIGPIPE
    (void) SIG_register (SIGPIPE, patch_cleanup);
#endif
#ifdef SIGTERM
    (void) SIG_register (SIGTERM, patch_cleanup);
#endif

    db = open_module ();
    for (i = 0; i < argc; i++)
	err += do_module (db, argv[i], PATCH, "Patching", patch_proc,
			  (char *) NULL, 0, 0, 0, (char *) NULL);
    close_module (db);
    free (options);
    patch_cleanup ();
    return (err);
}

/*
 * callback proc for doing the real work of patching
 */
/* ARGSUSED */
static char where[PATH_MAX];
static int
patch_proc (pargc, argv, xwhere, mwhere, mfile, shorten, local_specified,
	    mname, msg)
    int *pargc;
    char **argv;
    char *xwhere;
    char *mwhere;
    char *mfile;
    int shorten;
    int local_specified;
    char *mname;
    char *msg;
{
    int err = 0;
    int which;
    char repository[PATH_MAX];

    (void) sprintf (repository, "%s/%s", CVSroot, argv[0]);
    (void) strcpy (where, argv[0]);

    /* if mfile isn't null, we need to set up to do only part of the module */
    if (mfile != NULL)
    {
	char *cp;
	char path[PATH_MAX];

	/* if the portion of the module is a path, put the dir part on repos */
	if ((cp = strrchr (mfile, '/')) != NULL)
	{
	    *cp = '\0';
	    (void) strcat (repository, "/");
	    (void) strcat (repository, mfile);
	    (void) strcat (where, "/");
	    (void) strcat (where, mfile);
	    mfile = cp + 1;
	}

	/* take care of the rest */
	(void) sprintf (path, "%s/%s", repository, mfile);
	if (isdir (path))
	{
	    /* directory means repository gets the dir tacked on */
	    (void) strcpy (repository, path);
	    (void) strcat (where, "/");
	    (void) strcat (where, mfile);
	}
	else
	{
	    int i;

	    /* a file means muck argv */
	    for (i = 1; i < *pargc; i++)
		free (argv[i]);
	    argv[1] = xstrdup (mfile);
	    (*pargc) = 2;
	}
    }

    /* cd to the starting repository */
    if (chdir (repository) < 0)
    {
	error (0, errno, "cannot chdir to %s", repository);
	return (1);
    }

    if (force_tag_match)
	which = W_REPOS | W_ATTIC;
    else
	which = W_REPOS;

    if (rev1 != NULL && !rev1_validated)
    {
	tag_check_valid (rev1, *pargc - 1, argv + 1, local, 0, NULL);
	rev1_validated = 1;
    }
    if (rev2 != NULL && !rev2_validated)
    {
	tag_check_valid (rev2, *pargc - 1, argv + 1, local, 0, NULL);
	rev2_validated = 1;
    }

    /* start the recursion processor */
    err = start_recursion (patch_fileproc, (FILESDONEPROC) NULL, patch_dirproc,
			   (DIRLEAVEPROC) NULL, *pargc - 1, argv + 1, local,
			   which, 0, 1, where, 1, 1);

    return (err);
}

/*
 * Called to examine a particular RCS file, as appropriate with the options
 * that were set above.
 */
/* ARGSUSED */
static int
patch_fileproc (finfo)
    struct file_info *finfo;
{
    struct utimbuf t;
    char *vers_tag, *vers_head;
    char rcsspace[1][PATH_MAX];
    char *rcs = rcsspace[0];
    RCSNode *rcsfile;
    FILE *fp1, *fp2, *fp3;
    int ret = 0;
    int isattic = 0;
    int retcode = 0;
    char file1[PATH_MAX], file2[PATH_MAX], strippath[PATH_MAX];
    char *line1, *line2;
    size_t line1_chars_allocated;
    size_t line2_chars_allocated;
    char *cp1, *cp2;
    FILE *fp;

    /* find the parsed rcs file */
    if ((rcsfile = finfo->rcs) == NULL)
	return (1);
    if ((rcsfile->flags & VALID) && (rcsfile->flags & INATTIC))
	isattic = 1;

    (void) sprintf (rcs, "%s%s", finfo->file, RCSEXT);

    /* if vers_head is NULL, may have been removed from the release */
    if (isattic && rev2 == NULL && date2 == NULL)
	vers_head = NULL;
    else
	vers_head = RCS_getversion (rcsfile, rev2, date2, force_tag_match, 0);

    if (toptwo_diffs)
    {
	if (vers_head == NULL)
	    return (1);

	if (!date1)
	    date1 = xmalloc (50);	/* plenty big :-) */
	*date1 = '\0';
	if (RCS_getrevtime (rcsfile, vers_head, date1, 1) == -1)
	{
	    if (!really_quiet)
		error (0, 0, "cannot find date in rcs file %s revision %s",
		       rcs, vers_head);
	    return (1);
	}
    }
    vers_tag = RCS_getversion (rcsfile, rev1, date1, force_tag_match, 0);

    if (vers_tag == NULL && (vers_head == NULL || isattic))
	return (0);			/* nothing known about specified revs */

    if (vers_tag && vers_head && strcmp (vers_head, vers_tag) == 0)
	return (0);			/* not changed between releases */

    if (patch_short)
    {
	(void) printf ("File %s ", finfo->fullname);
	if (vers_tag == NULL)
	    (void) printf ("is new; current revision %s\n", vers_head);
	else if (vers_head == NULL)
	{
	    (void) printf ("is removed; not included in ");
	    if (rev2 != NULL)
		(void) printf ("release tag %s", rev2);
	    else if (date2 != NULL)
		(void) printf ("release date %s", date2);
	    else
		(void) printf ("current release");
	    (void) printf ("\n");
	}
	else
	    (void) printf ("changed from revision %s to %s\n",
			   vers_tag, vers_head);
	return (0);
    }
    if ((fp1 = fopen (tmpnam (tmpfile1), "w+")) != NULL)
	(void) fclose (fp1);
    if ((fp2 = fopen (tmpnam (tmpfile2), "w+")) != NULL)
	(void) fclose (fp2);
    if ((fp3 = fopen (tmpnam (tmpfile3), "w+")) != NULL)
	(void) fclose (fp3);
    if (fp1 == NULL || fp2 == NULL || fp3 == NULL)
    {
	error (0, 0, "cannot create temporary files");
	ret = 1;
	goto out;
    }
    if (vers_tag != NULL)
    {
	retcode = RCS_checkout (rcsfile->path, NULL, vers_tag, options, tmpfile1,
	                        0, 0);
	if (retcode != 0)
	{
	    if (!really_quiet)
		error (retcode == -1 ? 1 : 0, retcode == -1 ? errno : 0,
		       "co of revision %s in %s failed", vers_tag, rcs);
	    ret = 1;
	    goto out;
	}
	memset ((char *) &t, 0, sizeof (t));
	if ((t.actime = t.modtime = RCS_getrevtime (rcsfile, vers_tag,
						    (char *) 0, 0)) != -1)
		(void) utime (tmpfile1, &t);
    }
    else if (toptwo_diffs)
    {
	ret = 1;
	goto out;
    }
    if (vers_head != NULL)
    {
	retcode = RCS_checkout (rcsfile->path, NULL, vers_head, options, tmpfile2, 0, 0);
	if (retcode != 0)
	{
	    if (!really_quiet)
		error (retcode == -1 ? 1 : 0, retcode == -1 ? errno : 0,
		       "co of revision %s in %s failed", vers_head, rcs);
	    ret = 1;
	    goto out;
	}
	if ((t.actime = t.modtime = RCS_getrevtime (rcsfile, vers_head,
						    (char *) 0, 0)) != -1)
		(void) utime (tmpfile2, &t);
    }
    run_setup ("%s -%c", DIFF, unidiff ? 'u' : 'c');
    run_arg (tmpfile1);
    run_arg (tmpfile2);

    line1 = NULL;
    line1_chars_allocated = 0;
    line2 = NULL;
    line2_chars_allocated = 0;

    switch (run_exec (RUN_TTY, tmpfile3, RUN_TTY, RUN_REALLY))
    {
	case -1:			/* fork/wait failure */
	    error (1, errno, "fork for diff failed on %s", rcs);
	    break;
	case 0:				/* nothing to do */
	    break;
	case 1:
	    /*
	     * The two revisions are really different, so read the first two
	     * lines of the diff output file, and munge them to include more
	     * reasonable file names that "patch" will understand.
	     */

	    /* Output an "Index:" line for patch to use */
	    (void) fflush (stdout);
	    (void) printf ("Index: %s\n", finfo->fullname);
	    (void) fflush (stdout);

	    fp = open_file (tmpfile3, "r");
	    if (getline (&line1, &line1_chars_allocated, fp) < 0 ||
		getline (&line2, &line2_chars_allocated, fp) < 0)
	    {
		error (0, errno, "failed to read diff file header %s for %s",
		       tmpfile3, rcs);
		ret = 1;
		(void) fclose (fp);
		goto out;
	    }
	    if (!unidiff)
	    {
		if (strncmp (line1, "*** ", 4) != 0 ||
		    strncmp (line2, "--- ", 4) != 0 ||
		    (cp1 = strchr (line1, '\t')) == NULL ||
		    (cp2 = strchr (line2, '\t')) == NULL)
		{
		    error (0, 0, "invalid diff header for %s", rcs);
		    ret = 1;
		    (void) fclose (fp);
		    goto out;
		}
	    }
	    else
	    {
		if (strncmp (line1, "--- ", 4) != 0 ||
		    strncmp (line2, "+++ ", 4) != 0 ||
		    (cp1 = strchr (line1, '\t')) == NULL ||
		    (cp2 = strchr  (line2, '\t')) == NULL)
		{
		    error (0, 0, "invalid unidiff header for %s", rcs);
		    ret = 1;
		    (void) fclose (fp);
		    goto out;
		}
	    }
	    if (CVSroot != NULL)
		(void) sprintf (strippath, "%s/", CVSroot);
	    else
		(void) strcpy (strippath, REPOS_STRIP);
	    if (strncmp (rcs, strippath, strlen (strippath)) == 0)
		rcs += strlen (strippath);
	    if (vers_tag != NULL)
	    {
		(void) sprintf (file1, "%s:%s", finfo->fullname, vers_tag);
	    }
	    else
	    {
		(void) strcpy (file1, DEVNULL);
	    }
	    (void) sprintf (file2, "%s:%s", finfo->fullname,
			    vers_head ? vers_head : "removed");

	    /* Note that this prints "diff" not DIFF.  The format of a diff
	       does not depend on the name of the program which happens to
	       have produced it.  */
	    if (unidiff)
	    {
		(void) printf ("diff -u %s %s\n", file1, file2);
		(void) printf ("--- %s%s+++ ", file1, cp1);
	    }
	    else
	    {
		(void) printf ("diff -c %s %s\n", file1, file2);
		(void) printf ("*** %s%s--- ", file1, cp1);
	    }

	    (void) printf ("%s%s", finfo->fullname, cp2);
	    /* spew the rest of the diff out */
	    while (getline (&line1, &line1_chars_allocated, fp) >= 0)
		(void) fputs (line1, stdout);
	    (void) fclose (fp);
	    break;
	default:
	    error (0, 0, "diff failed for %s", finfo->fullname);
    }
  out:
    if (line1)
        free (line1);
    if (line2)
        free (line2);
    /* FIXME: should be checking for errors.  */
    (void) unlink (tmpfile1);
    (void) unlink (tmpfile2);
    (void) unlink (tmpfile3);
    return (ret);
}

/*
 * Print a warm fuzzy message
 */
/* ARGSUSED */
static Dtype
patch_dirproc (dir, repos, update_dir)
    char *dir;
    char *repos;
    char *update_dir;
{
    if (!quiet)
	error (0, 0, "Diffing %s", update_dir);
    return (R_PROCESS);
}

/*
 * Clean up temporary files
 */
static RETSIGTYPE
patch_cleanup ()
{
    if (tmpfile1[0] != '\0')
	(void) unlink_file (tmpfile1);
    if (tmpfile2[0] != '\0')
	(void) unlink_file (tmpfile2);
    if (tmpfile3[0] != '\0')
	(void) unlink_file (tmpfile3);
}