/*
 * Copyright 2005-2007 Gentoo Foundation
 * Distributed under the terms of the GNU General Public License v2
 * $Header: /var/cvsroot/gentoo-projects/portage-utils/q.c,v 1.43 2007/05/24 14:47:18 solar Exp $
 *
 * Copyright 2005-2007 Ned Ludd        - <solar@gentoo.org>
 * Copyright 2005-2007 Mike Frysinger  - <vapier@gentoo.org>
 */

#define Q_FLAGS "irmM:" COMMON_FLAGS
static struct option const q_long_opts[] = {
	{"install",      no_argument, NULL, 'i'},
	{"reinitialize", no_argument, NULL, 'r'},
	{"metacache",    no_argument, NULL, 'm'},
	{"modpath",       a_argument, NULL, 'M'},
	COMMON_LONG_OPTS
};
static const char *q_opts_help[] = {
	"Install symlinks for applets",
	"Reinitialize ebuild cache",
	"Reinitialize metadata cache",
	"Module path",
	COMMON_OPTS_HELP
};
static const char q_rcsid[] = "$Id: q.c,v 1.43 2007/05/24 14:47:18 solar Exp $";
#define q_usage(ret) usage(ret, Q_FLAGS, q_long_opts, q_opts_help, lookup_applet_idx("q"))

#ifndef STATIC
APPLET lookup_dl_applet(char *applet);
#endif

APPLET lookup_applet(char *applet);
APPLET lookup_applet(char *applet)
{
#ifndef STATIC
	APPLET dl_func;
#endif
	unsigned int i;

	if (strlen(applet) < 1)
		return NULL;

	for (i = 0; applets[i].name; ++i) {
		if (strcmp(applets[i].name, applet) == 0) {
			DBG("found applet %s at %p", applets[i].name, applets[i].func);
			argv0 = applets[i].name;
			if (i && applets[i].desc != NULL) ++argv0; /* chop the leading 'q' */
			return applets[i].func;
		}
	}

	/* No applet found? Search by shortname then... */
	DBG("Looking up applet (%s) by short name", applet);
	for (i = 1; applets[i].desc != NULL; ++i) {
		if (strcmp(applets[i].name + 1, applet) == 0) {
			DBG("found applet by short name %s", applets[i].name);
			argv0 = applets[i].name + 1;
			return applets[i].func;
		}
	}
#ifndef STATIC
	if ((dl_func = lookup_dl_applet(applet)) != NULL)
		return dl_func;
	if (*applet == 'q')
		if ((dl_func = lookup_dl_applet(applet+1)) != NULL)
			return dl_func;
#endif
	/* still nothing ?  those bastards ... */
	warn("Unknown applet '%s'", applet);
	return NULL;
}

#ifndef STATIC
APPLET lookup_dl_applet(char *applet) {
	char *ptr = NULL;
	APPLET iptr;
	FILE *fp;
	char buf[_Q_PATH_MAX];

	if (dlhandle != NULL)
		return NULL;

	/* modpath can be passed in as a global option */
	if (modpath == NULL) {
		DBG("opening /etc/q.conf");
		if ((fp = fopen("/etc/q.conf", "r")) == NULL)
			return NULL;

		while ((fgets(buf, sizeof(buf), fp)) != NULL) {
			rmspace(buf);
			remove_extra_space(buf);
			if ((strncmp(buf, "modpath=", 8)) == 0)
				modpath = &buf[8];
		}
		fclose(fp);
	}
	if (modpath == NULL)
		return NULL;

	if (!strlen(modpath))
		return NULL;

	DBG("module path set to %s", modpath);

	/* fill in the path, check that object exists and open it */
	xasprintf(&ptr, "%s/lib%s.so", modpath, applet);
	if ((access(ptr, X_OK)) != 0) {
		DBG("file does not exist or we dont have perms to mmap %s", ptr);
		free(ptr);
		return NULL;
	}
	if ((dlhandle = dlopen(ptr, RTLD_LAZY | RTLD_GLOBAL)) == NULL) {
		DBG("unable to load %s : %s", ptr, dlerror());
		free(ptr);
		return NULL;
	}
	free(ptr);

	xasprintf(&ptr, "%s_main", applet);
	DBG("symbol lookup %s", ptr);
	iptr = (APPLET) dlsym(dlhandle, ptr);
	free(ptr);
	module_name = applet;
	return iptr;
}
#endif

int lookup_applet_idx(const char *applet)
{
	unsigned int i;
	for (i = 0; applets[i].name; i++)
		if (strcmp(applets[i].name, applet) == 0)
			return i;
	return 0;
}

int q_main(int argc, char **argv)
{
	int i;
	char *p;
	APPLET func;

	if (argc == 0)
		return 1;

	argv0 = p = basename(argv[0]);

	if ((func = lookup_applet(p)) == NULL)
		return 1;
	if (strcmp("q", p) != 0)
		return (func)(argc, argv);

	if (argc == 1)
		q_usage(EXIT_FAILURE);

	while ((i = GETOPT_LONG(Q, q, "+")) != -1) {
		switch (i) {
		COMMON_GETOPTS_CASES(q)
		case 'M': modpath = optarg; break;
		case 'm': reinitialize_metacache = 1; break;
		case 'r': reinitialize = 1; break;
		case 'i': {
			char buf[_Q_PATH_MAX];
			/* always bzero a buffer before using readlink() */
			memset(buf, 0x00, sizeof(buf));
			printf("Installing symlinks:\n");
			if ((readlink("/proc/self/exe", buf, sizeof(buf))) == (-1)) {
				warnfp("could not readlink '/proc/self/exe'");
				return 1;
			}
			if (chdir(dirname(buf)) != 0) {
				warnfp("could not chdir to '%s'", buf);
				return 1;
			}
			for (i = 1; applets[i].desc != NULL; ++i) {
				printf(" %s ...", applets[i].name);
				errno = 0;
				symlink("q", applets[i].name);
				printf("\t[%s]\n", strerror(errno));
			}
			return 0;
		}
		}
	}
	if (reinitialize || reinitialize_metacache)
		return 0;
	if (argc == optind)
		q_usage(EXIT_FAILURE);
	if ((func = lookup_applet(argv[optind])) == NULL)
		return 1;

	/* In case of "q --option ... appletname ...", remove appletname from the
	 * applet's args, exchange "appletname" and "--option". */
	if (optind > 1) {
		char* appletname = argv[optind];
		argv[optind] = argv[1];
		argv[1] = appletname;
	}

	optind = 0; /* reset so the applets can call getopt */

	return (func)(argc - 1, ++argv);
}