/*
 * (C) 2014-2020 by Christian Hesse <mail@eworm.de>
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 * compile with:
 * $ gcc -o ykfde-cpio ykfde-cpio.c -larchive
 */

#include <dirent.h>
#include <fcntl.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>

#include <archive.h>
#include <archive_entry.h>

#include "../config.h"
#include "../version.h"

#define PROGNAME "ykfde-cpio"

const static char optstring[] = "hV";
const static struct option options_long[] = {
	/* name			has_arg			flag	val */
	{ "help",		no_argument,		NULL,	'h' },
	{ "version",		no_argument,		NULL,	'V' },
	{ 0, 0, 0, 0 }
};

int add_dir(struct archive *archive, const char * path) {
	struct stat st;
	struct archive_entry *entry;
	int8_t rc = EXIT_FAILURE;

	/* initialize struct stat for directories from root */
	if (stat("/", &st) < 0) {
		perror("stat() failed");
		goto out;
	}

	if ((entry = archive_entry_new()) == NULL) {
		fprintf(stderr, "archive_entry_new() failed");
		goto out;
	}

	archive_entry_set_pathname(entry, path);
	archive_entry_set_filetype(entry, AE_IFDIR);
	archive_entry_copy_stat(entry, &st);
	if (archive_write_header(archive, entry) != ARCHIVE_OK) {
		fprintf(stderr, "archive_write_header() failed");
		goto out;
	}
	archive_entry_free(entry);

	rc = EXIT_SUCCESS;

out:
	return rc;
}

int main(int argc, char **argv) {
	int i;
	unsigned int version = 0, help = 0;
	char cpiotmpfile[] = CPIOTMPFILE;
	struct archive *archive;
	struct archive_entry *entry;
	struct stat st;
	char buff[64];
	int len, fdfile, fdarchive;
	DIR * dir;
	struct dirent * ent;
	char * filename, * path;
	off_t pathlength = 0;
	int8_t rc = EXIT_FAILURE;

	/* get command line options */
	while ((i = getopt_long(argc, argv, optstring, options_long, NULL)) != -1)
		switch (i) {
			case 'h':
				help++;
				break;
			case 'V':
				version++;
				break;
		}

	if (version > 0)
		printf("%s: %s v%s (compiled: " __DATE__ ", " __TIME__ ")\n", argv[0], PROGNAME, VERSION);

	if (help > 0)
		fprintf(stderr, "usage: %s [-h|--help] [-V|--version]\n", argv[0]);

	if (version > 0 || help > 0)
		return EXIT_SUCCESS;

	if ((fdarchive = mkstemp(cpiotmpfile)) < 0) {
		perror("mkstemp() failed");
		goto out10;
	}

	if ((archive = archive_write_new()) == NULL) {
		fprintf(stderr, "archive_write_new() failed.\n");
		goto out10;
	}

	if (archive_write_set_format_cpio_newc(archive) != ARCHIVE_OK) {
		fprintf(stderr, "archive_write_set_format_cpio_newc() failed.\n");
		goto out10;
	}

	if (archive_write_open_fd(archive, fdarchive) != ARCHIVE_OK) {
		fprintf(stderr, "archive_write_open_fd() failed.\n");
		goto out10;
	}

	while (1) {
		path = strdup(CHALLENGEDIR + 1);
		if (strstr(path + pathlength, "/") == NULL)
			break;

		*strstr(path + pathlength, "/") = 0;
		pathlength = strlen(path) + 1;

		if (add_dir(archive, path) < 0) {
			fprintf(stderr, "add_dir() failed");
			goto out10;
		}

		free(path);
	}

	if ((dir = opendir(CHALLENGEDIR)) == NULL) {
		perror("opendir() failed");
		goto out10;
	}

	while ((ent = readdir(dir)) != NULL) {
		filename = malloc(sizeof(CHALLENGEDIR) + strlen(ent->d_name) + 1);
		sprintf(filename, CHALLENGEDIR "%s", ent->d_name);

		if (stat(filename, &st) < 0) {
			perror("stat() failed");
			goto out10;
		}

		if (S_ISREG(st.st_mode)) {
			if ((entry = archive_entry_new()) == NULL) {
				fprintf(stderr, "archive_entry_new() failed.\n");
				goto out10;
			}

			/* these do not return exit code */
			archive_entry_set_pathname(entry, filename + 1);
			archive_entry_set_size(entry, st.st_size);
			archive_entry_set_filetype(entry, AE_IFREG);
			archive_entry_set_perm(entry, 0644);

			if (archive_write_header(archive, entry) != ARCHIVE_OK) {
				fprintf(stderr, "archive_write_header() failed");
				goto out10;
			}

			if ((fdfile = open(filename, O_RDONLY)) < 0) {
				perror("open() failed");
				goto out10;
			}

			if ((len = read(fdfile, buff, sizeof(buff))) < 0) {
				perror("read() failed");
				goto out10;
			}

			while (len > 0) {
				if (archive_write_data(archive, buff, len) < 0) {
					fprintf(stderr, "archive_write_data() failed");
					goto out10;
				}

				if ((len = read(fdfile, buff, sizeof(buff))) < 0) {
					perror("read() failed");
					goto out10;
				}
			}

			if (close(fdfile) < 0) {
				perror("close() failed");
				goto out10;
			}

			archive_entry_free(entry);
		}
		free(filename);
	}

	if (closedir(dir) < 0) {
		perror("closedir() failed");
		goto out10;
	}

	if (archive_write_close(archive) != ARCHIVE_OK) {
		fprintf(stderr, "archive_write_close() failed");
		goto out10;
	}

	if (archive_write_free(archive) != ARCHIVE_OK) {
		fprintf(stderr, "archive_write_free() failed");
		goto out10;
	}

	if (access(CPIOFILE, F_OK) == 0 && unlink(CPIOFILE) < 0) {
		perror("unkink() failed");
		goto out10;
	}

	if (rename(cpiotmpfile, CPIOFILE) < 0) {
		perror("rename() failed");
		goto out10;
	}

	rc = EXIT_SUCCESS;

out10:
	if (access(cpiotmpfile, F_OK) == 0)
		unlink(cpiotmpfile);

	return rc;
}

// vim: set syntax=c: