/*
  modify.c -- test tool for modifying zip archive in multiple ways
  Copyright (C) 2012-2015 Dieter Baron and Thomas Klausner

  This file is part of libzip, a library to manipulate ZIP archives.
  The authors can be contacted at <libzip@nih.at>

  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. The names of the authors may not be used to endorse or promote
     products derived from this software without specific prior
     written permission.
 
  THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``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 AUTHORS 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.
*/

#include "config.h"

#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <inttypes.h>
#ifdef _WIN32
/* WIN32 needs <fcntl.h> for _O_BINARY */
#include <fcntl.h>
#endif

#ifndef HAVE_GETOPT
#include "getopt.h"
#endif

#include "zip.h"

zip_source_t *source_hole_create(const char *, int flags, zip_error_t *);

typedef enum {
    SOURCE_TYPE_NONE,
    SOURCE_TYPE_IN_MEMORY,
    SOURCE_TYPE_HOLE
} source_type_t;

typedef struct dispatch_table_s {
    const char *cmdline_name;
    int argument_count;
    const char *arg_names;
    const char *description;
    int (*function)(int argc, char *argv[]);
} dispatch_table_t;

static zip_flags_t get_flags(const char *arg);
static zip_int32_t get_compression_method(const char *arg);
static void hexdump(const zip_uint8_t *data, zip_uint16_t len);
static zip_t *read_to_memory(const char *archive, int flags, int *err, zip_source_t **srcp);
static zip_source_t *source_nul(zip_t *za, zip_uint64_t length);

zip_t *za, *z_in[16];
unsigned int z_in_count;
zip_flags_t stat_flags;

static int
add(int argc, char *argv[]) {
    zip_source_t *zs;

    if ((zs=zip_source_buffer(za, argv[1], strlen(argv[1]), 0)) == NULL) {
	fprintf(stderr, "can't create zip_source from buffer: %s\n", zip_strerror(za));
	return -1;
    }

    if (zip_add(za, argv[0], zs) == -1) {
	zip_source_free(zs);
	fprintf(stderr, "can't add file '%s': %s\n", argv[0], zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
add_dir(int argc, char *argv[]) {
    /* add directory */
    if (zip_add_dir(za, argv[0]) < 0) {
	fprintf(stderr, "can't add directory '%s': %s\n", argv[0], zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
add_file(int argc, char *argv[]) {
    zip_source_t *zs;
    zip_uint64_t start = strtoull(argv[2], NULL, 10);
    zip_int64_t len = strtoll(argv[3], NULL, 10);

    if (strcmp(argv[1], "/dev/stdin") == 0) {
	if ((zs=zip_source_filep(za, stdin, start, len)) == NULL) {
	    fprintf(stderr, "can't create zip_source from stdin: %s\n", zip_strerror(za));
	    return -1;
	}
    } else {
	if ((zs=zip_source_file(za, argv[1], start, len)) == NULL) {
	    fprintf(stderr, "can't create zip_source from file: %s\n", zip_strerror(za));
	    return -1;
	}
    }

    if (zip_add(za, argv[0], zs) == -1) {
	zip_source_free(zs);
	fprintf(stderr, "can't add file '%s': %s\n", argv[0], zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
add_from_zip(int argc, char *argv[]) {
    zip_uint64_t idx;
    int err;
    zip_source_t *zs;
    /* add from another zip file */
    idx = strtoull(argv[2], NULL, 10);
    zip_uint64_t start = strtoull(argv[3], NULL, 10);
    zip_int64_t len = strtoll(argv[4], NULL, 10);
    if ((z_in[z_in_count]=zip_open(argv[1], ZIP_CHECKCONS, &err)) == NULL) {
	zip_error_t error;
	zip_error_init_with_code(&error, err);
	fprintf(stderr, "can't open zip archive '%s': %s\n", argv[1], zip_error_strerror(&error));
	zip_error_fini(&error);
	return -1;
    }
    if ((zs=zip_source_zip(za, z_in[z_in_count], idx, 0, start, len)) == NULL) {
	fprintf(stderr, "error creating file source from '%s' index '%" PRIu64 "': %s\n", argv[1], idx, zip_strerror(za));
	zip_close(z_in[z_in_count]);
	return -1;
    }
    if (zip_add(za, argv[0], zs) == -1) {
	fprintf(stderr, "can't add file '%s': %s\n", argv[0], zip_strerror(za));
	zip_source_free(zs);
	zip_close(z_in[z_in_count]);
	return -1;
    }
    z_in_count++;
    return 0;
}

static int
add_nul(int argc, char *argv[]) {
    zip_source_t *zs;
    zip_uint64_t length = strtoull(argv[1], NULL, 10);
    
    if ((zs=source_nul(za, length)) == NULL) {
        fprintf(stderr, "can't create zip_source for length: %s\n", zip_strerror(za));
        return -1;
    }
    
    if (zip_add(za, argv[0], zs) == -1) {
        zip_source_free(zs);
        fprintf(stderr, "can't add file '%s': %s\n", argv[0], zip_strerror(za));
        return -1;
    }
    return 0;
}

static int
cat(int argc, char *argv[]) {
    /* output file contents to stdout */
    zip_uint64_t idx;
    zip_int64_t n;
    zip_file_t *zf;
    char buf[8192];
    int err;
    idx = strtoull(argv[0], NULL, 10);

#ifdef _WIN32
    /* Need to set stdout to binary mode for Windows */
    setmode(fileno(stdout), _O_BINARY);
#endif
    if ((zf=zip_fopen_index(za, idx, 0)) == NULL) {
	fprintf(stderr, "can't open file at index '%" PRIu64 "': %s\n", idx, zip_strerror(za));
	return -1;
    }
    while ((n=zip_fread(zf, buf, sizeof(buf))) > 0) {
	if (fwrite(buf, (size_t)n, 1, stdout) != 1) {
	    zip_fclose(zf);
	    fprintf(stderr, "can't write file contents to stdout: %s\n", strerror(errno));
	    return -1;
	}
    }
    if (n == -1) {
	zip_fclose(zf);
	fprintf(stderr, "can't read file at index '%" PRIu64 "': %s\n", idx, zip_file_strerror(zf));
	return -1;
    }
    if ((err = zip_fclose(zf)) != 0) {
	zip_error_t error;
	
	zip_error_init_with_code(&error, err);
	fprintf(stderr, "can't close file at index '%" PRIu64 "': %s\n", idx, zip_error_strerror(&error));
	return -1;
    }

    return 0;
}

static int
count_extra(int argc, char *argv[]) {
    zip_int16_t count;
    zip_uint64_t idx;
    zip_flags_t ceflags = 0;
    idx = strtoull(argv[0], NULL, 10);
    ceflags = get_flags(argv[1]);
    if ((count=zip_file_extra_fields_count(za, idx, ceflags)) < 0) {
	fprintf(stderr, "can't get extra field count for file at index '%" PRIu64 "': %s\n", idx, zip_strerror(za));
	return -1;
    } else {
	printf("Extra field count: %d\n", count);
    }
    return 0;
}

static int
count_extra_by_id(int argc, char *argv[]) {
    zip_int16_t count;
    zip_uint16_t eid;
    zip_flags_t ceflags = 0;
    zip_uint64_t idx;
    idx = strtoull(argv[0], NULL, 10);
    eid = (zip_uint16_t)strtoull(argv[1], NULL, 10);
    ceflags = get_flags(argv[2]);
    if ((count=zip_file_extra_fields_count_by_id(za, idx, eid, ceflags)) < 0) {
	fprintf(stderr, "can't get extra field count for file at index '%" PRIu64 "' and for id `%d': %s\n", idx, eid, zip_strerror(za));
	return -1;
    } else {
	printf("Extra field count: %d\n", count);
    }
    return 0;
}

static int
delete(int argc, char *argv[]) {
    zip_uint64_t idx;
    idx = strtoull(argv[0], NULL, 10);
    if (zip_delete(za, idx) < 0) {
	fprintf(stderr, "can't delete file at index '%" PRIu64 "': %s\n", idx, zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
delete_extra(int argc, char *argv[]) {
    zip_flags_t geflags;
    zip_uint16_t eid;
    zip_uint64_t idx;
    idx = strtoull(argv[0], NULL, 10);
    eid = (zip_uint16_t)strtoull(argv[1], NULL, 10);
    geflags = get_flags(argv[2]);
    if ((zip_file_extra_field_delete(za, idx, eid, geflags)) < 0) {
	fprintf(stderr, "can't delete extra field data for file at index '%" PRIu64 "', extra field id `%d': %s\n", idx, eid, zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
delete_extra_by_id(int argc, char *argv[]) {
    zip_flags_t geflags;
    zip_uint16_t eid, eidx;
    zip_uint64_t idx;
    idx = strtoull(argv[0], NULL, 10);
    eid = (zip_uint16_t)strtoull(argv[1], NULL, 10);
    eidx = (zip_uint16_t)strtoull(argv[2], NULL, 10);
    geflags = get_flags(argv[3]);
    if ((zip_file_extra_field_delete_by_id(za, idx, eid, eidx, geflags)) < 0) {
	fprintf(stderr, "can't delete extra field data for file at index '%" PRIu64 "', extra field id `%d', extra field idx `%d': %s\n", idx, eid, eidx, zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
get_archive_comment(int argc, char *argv[]) {
    const char *comment;
    int len;
    /* get archive comment */
    if ((comment=zip_get_archive_comment(za, &len, 0)) == NULL)
	printf("No archive comment\n");
    else
	printf("Archive comment: %.*s\n", len, comment);
    return 0;
}

static int
get_extra(int argc, char *argv[]) {
    zip_flags_t geflags;
    zip_uint16_t id, eidx, eflen;
    const zip_uint8_t *efdata;
    zip_uint64_t idx;
    /* get extra field data */
    idx = strtoull(argv[0], NULL, 10);
    eidx = (zip_uint16_t)strtoull(argv[1], NULL, 10);
    geflags = get_flags(argv[2]);
    if ((efdata=zip_file_extra_field_get(za, idx, eidx, &id, &eflen, geflags)) == NULL) {
	fprintf(stderr, "can't get extra field data for file at index %" PRIu64 ", extra field %d, flags %u: %s\n", idx, eidx, geflags, zip_strerror(za));
	return -1;
    }
    printf("Extra field 0x%04x: len %d", id, eflen);
    if (eflen > 0) {
	printf(", data ");
	hexdump(efdata, eflen);
    }
    printf("\n");
    return 0;
}

static int
get_extra_by_id(int argc, char *argv[]) {
    zip_flags_t geflags;
    zip_uint16_t eid, eidx, eflen;
    const zip_uint8_t *efdata;
    zip_uint64_t idx;
    idx = strtoull(argv[0], NULL, 10);
    eid = (zip_uint16_t)strtoull(argv[1], NULL, 10);
    eidx = (zip_uint16_t)strtoull(argv[2], NULL, 10);
    geflags = get_flags(argv[3]);
    if ((efdata=zip_file_extra_field_get_by_id(za, idx, eid, eidx, &eflen, geflags)) == NULL) {
	fprintf(stderr, "can't get extra field data for file at index %" PRIu64 ", extra field id %d, ef index %d, flags %u: %s\n", idx, eid, eidx, geflags, zip_strerror(za));
	return -1;
    }
    printf("Extra field 0x%04x: len %d", eid, eflen);
    if (eflen > 0) {
	printf(", data ");
	hexdump(efdata, eflen);
    }
    printf("\n");
    return 0;
}

static int
get_file_comment(int argc, char *argv[]) {
    const char *comment;
    int len;
    zip_uint64_t idx;
    /* get file comment */
    idx = strtoull(argv[0], NULL, 10);
    if ((comment=zip_get_file_comment(za, idx, &len, 0)) == NULL) {
	fprintf(stderr, "can't get comment for '%s': %s\n", zip_get_name(za, idx, 0), zip_strerror(za));
	return -1;
    } else if (len == 0)
	printf("No comment for '%s'\n", zip_get_name(za, idx, 0));
    else
	printf("File comment for '%s': %.*s\n", zip_get_name(za, idx, 0), len, comment);
    return 0;
}

static int
name_locate(int argc, char *argv[]) {
    zip_flags_t flags;
    zip_int64_t idx;
    flags = get_flags(argv[1]);

    if ((idx=zip_name_locate(za, argv[0], flags)) < 0) {
	fprintf(stderr, "can't find entry with name '%s' using flags '%s'\n", argv[0], argv[1]);
    } else {
	printf("name '%s' using flags '%s' found at index %" PRId64 "\n", argv[0], argv[1], idx);
    }	

    return 0;
}

static int
zrename(int argc, char *argv[]) {
    zip_uint64_t idx;
    idx = strtoull(argv[0], NULL, 10);
    if (zip_rename(za, idx, argv[1]) < 0) {
	fprintf(stderr, "can't rename file at index '%" PRIu64 "' to `%s': %s\n", idx, argv[1], zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
replace_file_contents(int argc, char *argv[]) {
    /* replace file contents with data from command line */
    const char *content;
    zip_source_t *s;
    zip_uint64_t idx;
    idx = strtoull(argv[0], NULL, 10);
    content = argv[1];
    if ((s=zip_source_buffer(za, content, strlen(content), 0)) == NULL ||
	zip_file_replace(za, idx, s, 0) < 0) {
	zip_source_free(s);
	fprintf(stderr, "error replacing file data: %s\n", zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
set_extra(int argc, char *argv[]) {
    zip_flags_t geflags;
    zip_uint16_t eid, eidx;
    const zip_uint8_t *efdata;
    zip_uint64_t idx;
    idx = strtoull(argv[0], NULL, 10);
    eid = (zip_uint16_t)strtoull(argv[1], NULL, 10);
    eidx = (zip_uint16_t)strtoull(argv[2], NULL, 10);
    geflags = get_flags(argv[3]);
    efdata = (zip_uint8_t *)argv[4];
    if ((zip_file_extra_field_set(za, idx, eid, eidx, efdata, (zip_uint16_t)strlen((const char *)efdata), geflags)) < 0) {
	fprintf(stderr, "can't set extra field data for file at index '%" PRIu64 "', extra field id `%d', index `%d': %s\n", idx, eid, eidx, zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
set_archive_comment(int argc, char *argv[]) {
    if (zip_set_archive_comment(za, argv[0], (zip_uint16_t)strlen(argv[0])) < 0) {
	fprintf(stderr, "can't set archive comment to `%s': %s\n", argv[0], zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
set_file_comment(int argc, char *argv[]) {
    zip_uint64_t idx;
    idx = strtoull(argv[0], NULL, 10);
    if (zip_file_set_comment(za, idx, argv[1], (zip_uint16_t)strlen(argv[1]), 0) < 0) {
	fprintf(stderr, "can't set file comment at index '%" PRIu64 "' to `%s': %s\n", idx, argv[1], zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
set_file_compression(int argc, char *argv[]) {
    zip_int32_t method;
    zip_uint32_t flags;
    zip_uint64_t idx;
    idx = strtoull(argv[0], NULL, 10);
    method = get_compression_method(argv[1]);
    flags = (zip_uint32_t)strtoull(argv[2], NULL, 10);
    if (zip_set_file_compression(za, idx, method, flags) < 0) {
	fprintf(stderr, "can't set file compression method at index '%" PRIu64 "' to `%s', flags `%d': %s\n", idx, argv[1], flags, zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
set_file_mtime(int argc, char *argv[]) {
    /* set file last modification time (mtime) */
    time_t mtime;
    zip_uint64_t idx;
    idx = strtoull(argv[0], NULL, 10);
    mtime = (time_t)strtoull(argv[1], NULL, 10);
    if (zip_file_set_mtime(za, idx, mtime, 0) < 0) {
	fprintf(stderr, "can't set file mtime at index '%" PRIu64 "' to `%ld': %s\n", idx, mtime, zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
set_password(int argc, char *argv[]) {
    /* set default password */
    if (zip_set_default_password(za, argv[0]) < 0) {
	fprintf(stderr, "can't set default password to `%s'", argv[0]);
	return -1;
    }
    return 0;
}

static int
zstat(int argc, char *argv[]) {
    zip_uint64_t idx;
    char buf[100];
    struct zip_stat sb;
    idx = strtoull(argv[0], NULL, 10);

    if (zip_stat_index(za, idx, stat_flags, &sb) < 0) {
	fprintf(stderr, "zip_stat_index failed on '%" PRIu64 "' failed: %s\n", idx, zip_strerror(za));
	return -1;
    }

    if (sb.valid & ZIP_STAT_NAME)
	printf("name: '%s'\n", sb.name);
    if (sb.valid & ZIP_STAT_INDEX)
	printf("index: '%"PRIu64"'\n", sb.index);
    if (sb.valid & ZIP_STAT_SIZE)
	printf("size: '%"PRIu64"'\n", sb.size);
    if (sb.valid & ZIP_STAT_COMP_SIZE)
	printf("compressed size: '%"PRIu64"'\n", sb.comp_size);
    if (sb.valid & ZIP_STAT_MTIME) {
	struct tm *tpm;
	tpm = localtime(&sb.mtime);
	strftime(buf, sizeof(buf), "%a %b %d %Y %H:%M:%S", tpm);
	printf("mtime: '%s'\n", buf);
    }
    if (sb.valid & ZIP_STAT_CRC)
	printf("crc: '%0x'\n", sb.crc);
    if (sb.valid & ZIP_STAT_COMP_METHOD)
	printf("compression method: '%d'\n", sb.comp_method);
    if (sb.valid & ZIP_STAT_ENCRYPTION_METHOD)
	printf("encryption method: '%d'\n", sb.encryption_method);
    if (sb.valid & ZIP_STAT_FLAGS)
	printf("flags: '%ld'\n", (long)sb.flags);
    printf("\n");

    return 0;
}

static int
unchange_all(int argc, char *argv[]) {
    if (zip_unchange_all(za) < 0) {
	fprintf(stderr, "can't revert changes to archive: %s\n", zip_strerror(za));
	return -1;
    }
    return 0;
}

static int
zin_close(int argc, char *argv[]) {
    zip_uint64_t idx;

    idx = strtoull(argv[0], NULL, 10);
    if (idx >= z_in_count) {
	fprintf(stderr, "invalid argument '%" PRIu64 "', only %d zip sources open\n", idx, z_in_count);
	return -1;
    }
    if (zip_close(z_in[idx]) < 0) {
	fprintf(stderr, "can't close source archive: %s\n", zip_strerror(z_in[idx]));
	return -1;
    }
    z_in[idx] = z_in[z_in_count];
    z_in_count--;

    return 0;
}

static zip_flags_t
get_flags(const char *arg)
{
    zip_flags_t flags = 0;
    if (strchr(arg, 'C') != NULL)
	flags |= ZIP_FL_NOCASE;
    if (strchr(arg, 'c') != NULL)
	flags |= ZIP_FL_CENTRAL;
    if (strchr(arg, 'd') != NULL)
	flags |= ZIP_FL_NODIR;
    if (strchr(arg, 'l') != NULL)
	flags |= ZIP_FL_LOCAL;
    if (strchr(arg, 'u') != NULL)
	flags |= ZIP_FL_UNCHANGED;
    return flags;
}

static zip_int32_t
get_compression_method(const char *arg)
{
    if (strcmp(arg, "default") == 0)
        return ZIP_CM_DEFAULT;
    else if (strcmp(arg, "store") == 0)
        return ZIP_CM_STORE;
    else if (strcmp(arg, "deflate") ==0)
        return ZIP_CM_DEFLATE;
    else if (strcmp(arg, "unknown") ==0)
        return 99;
    return 0; /* TODO: error handling */
}

static void
hexdump(const zip_uint8_t *data, zip_uint16_t len)
{
    zip_uint16_t i;

    if (len <= 0)
	return;

    printf("0x");
	
    for (i=0; i<len; i++)
	printf("%02x", data[i]);

    return;    
}


static zip_t *
read_hole(const char *archive, int flags, int *err)
{
    zip_error_t error;
    zip_source_t *src = NULL;
    zip_t *zs = NULL;
    
    zip_error_init(&error);
    
    if ((src = source_hole_create(archive, flags, &error)) == NULL
        || (zs = zip_open_from_source(src, flags, &error)) == NULL) {
        zip_source_free(src);
        *err = zip_error_code_zip(&error);
        errno = zip_error_code_system(&error);
    }
    
    return zs;
}


static zip_t *
read_to_memory(const char *archive, int flags, int *err, zip_source_t **srcp)
{
    struct stat st;
    zip_source_t *src;
    zip_t *zb;
    zip_error_t error;

    if (stat(archive, &st) < 0) {
	if (errno == ENOENT) {
	    src = zip_source_buffer_create(NULL, 0, 0, &error);
	}
	else {
	    *err = ZIP_ER_OPEN;
	    return NULL;
	}
    }
    else {
	char *buf;
	FILE *fp;
	if ((buf=malloc((size_t)st.st_size)) == NULL) {
	    *err = ZIP_ER_MEMORY;
	    return NULL;
	}
	if ((fp=fopen(archive, "r")) == NULL) {
	    free(buf);
	    *err = ZIP_ER_READ;
	    return NULL;
	}
	if (fread(buf, (size_t)st.st_size, 1, fp) < 1) {
	    free(buf);
	    fclose(fp);
	    *err = ZIP_ER_READ;
	    return NULL;
	}
	fclose(fp);
	src = zip_source_buffer_create(buf, (zip_uint64_t)st.st_size, 1, &error);
	if (src == NULL) {
	    free(buf);
	}
    }
    if (src == NULL) {
	*err = zip_error_code_zip(&error);
	errno = zip_error_code_system(&error);
	return NULL;
    }
    zb = zip_open_from_source(src, flags, &error);
    if (zb == NULL) {
	*err = zip_error_code_zip(&error);
	errno = zip_error_code_system(&error);
	zip_source_free(src);
	return NULL;
    }
    zip_source_keep(src);
    *srcp = src;
    return zb;
}


typedef struct source_nul {
    zip_error_t error;
    zip_uint64_t length;
    zip_uint64_t offset;
} source_nul_t;

static zip_int64_t
source_nul_cb(void *ud, void *data, zip_uint64_t length, zip_source_cmd_t command)
{
    source_nul_t *ctx = (source_nul_t *)ud;
    
    switch (command) {
        case ZIP_SOURCE_CLOSE:
            return 0;

        case ZIP_SOURCE_ERROR:
            return zip_error_to_data(&ctx->error, data, length);
            
        case ZIP_SOURCE_FREE:
            free(ctx);
            return 0;
            
        case ZIP_SOURCE_OPEN:
            ctx->offset = 0;
            return 0;
            
        case ZIP_SOURCE_READ:
	    if (length > ZIP_INT64_MAX) {
		zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
		return -1;
	    }

            if (length > ctx->length - ctx->offset) {
                length =ctx->length - ctx->offset;
            }
            
            memset(data, 0, length);
            ctx->offset += length;
            return (zip_int64_t)length;
            
        case ZIP_SOURCE_STAT: {
            zip_stat_t *st = ZIP_SOURCE_GET_ARGS(zip_stat_t, data, length, &ctx->error);
            
            if (st == NULL) {
                return -1;
            }
            
            st->valid |= ZIP_STAT_SIZE;
            st->size = ctx->length;
            
            return 0;
        }
            
        case ZIP_SOURCE_SUPPORTS:
            return zip_source_make_command_bitmap(ZIP_SOURCE_CLOSE, ZIP_SOURCE_ERROR, ZIP_SOURCE_FREE, ZIP_SOURCE_OPEN, ZIP_SOURCE_READ, ZIP_SOURCE_STAT, -1);

        default:
            zip_error_set(&ctx->error, ZIP_ER_OPNOTSUPP, 0);
            return -1;
    }
}

static zip_source_t *
source_nul(zip_t *zs, zip_uint64_t length)
{
    source_nul_t *ctx;
    zip_source_t *src;
    
    if ((ctx = (source_nul_t *)malloc(sizeof(*ctx))) == NULL) {
        zip_error_set(zip_get_error(zs), ZIP_ER_MEMORY, 0);
        return NULL;
    }
    
    zip_error_init(&ctx->error);
    ctx->length = length;
    ctx->offset = 0;
    
    if ((src = zip_source_function(zs, source_nul_cb, ctx)) == NULL) {
        free(ctx);
        return NULL;
    }
    
    return src;
}


static int
write_memory_src_to_file(const char *archive, zip_source_t *src)
{
    zip_stat_t zst;
    char *buf;
    FILE *fp;

    if (zip_source_stat(src, &zst) < 0) {
	fprintf(stderr, "zip_source_stat on buffer failed: %s\n", zip_error_strerror(zip_source_error(src)));
	return -1;
    }
    if (zip_source_open(src) < 0) {
	if (zip_error_code_zip(zip_source_error(src)) == ZIP_ER_DELETED) {
	    if (remove(archive) < 0 && errno != ENOENT) {
		fprintf(stderr, "remove failed: %s\n", strerror(errno));
		return -1;
	    }
	    return 0;
	}
	fprintf(stderr, "zip_source_open on buffer failed: %s\n", zip_error_strerror(zip_source_error(src)));
	return -1;
    }
    if ((buf=malloc(zst.size)) == NULL) {
	fprintf(stderr, "malloc failed: %s\n", strerror(errno));
	zip_source_close(src);
	return -1;
    }
    if (zip_source_read(src, buf, zst.size) < (zip_int64_t)zst.size) {
	fprintf(stderr, "zip_source_read on buffer failed: %s\n", zip_error_strerror(zip_source_error(src)));
	zip_source_close(src);
	free(buf);
	return -1;
    }
    zip_source_close(src);
    if ((fp=fopen(archive, "wb")) == NULL) {
	fprintf(stderr, "fopen failed: %s\n", strerror(errno));
	free(buf);
	return -1;
    }
    if (fwrite(buf, zst.size, 1, fp) < 1) {
	fprintf(stderr, "fwrite failed: %s\n", strerror(errno));
	free(buf);
	fclose(fp);
	return -1;
    }
    free(buf);
    if (fclose(fp) != 0) {
	fprintf(stderr, "fclose failed: %s\n", strerror(errno));
	return -1;
    }
    return 0;
}

dispatch_table_t dispatch_table[] = {
    { "add", 2, "name content", "add file called name using content", add },
    { "add_dir", 1, "name", "add directory", add_dir },
    { "add_file", 4, "name file_to_add offset len", "add file to archive, len bytes starting from offset", add_file },
    { "add_from_zip", 5, "name archivename index offset len", "add file from another archive, len bytes starting from offset", add_from_zip },
    { "add_nul", 2, "name length", "add NUL bytes", add_nul },
    { "cat", 1, "index", "output file contents to stdout", cat },
    { "count_extra", 2, "index flags", "show number of extra fields for archive entry", count_extra },
    { "count_extra_by_id", 3, "index extra_id flags", "show number of extra fields of type extra_id for archive entry", count_extra_by_id },
    { "delete", 1, "index", "remove entry", delete },
    { "delete_extra", 3, "index extra_idx flags", "remove extra field", delete_extra },
    { "delete_extra_by_id", 4, "index extra_id extra_index flags", "remove extra field of type extra_id", delete_extra_by_id },
    { "get_archive_comment", 0, "", "show archive comment", get_archive_comment },
    { "get_extra", 3, "index extra_index flags", "show extra field", get_extra },
    { "get_extra_by_id", 4, "index extra_id extra_index flags", "show extra field of type extra_id", get_extra_by_id },
    { "get_file_comment", 1, "index", "get file comment", get_file_comment },
    { "name_locate", 2, "name flags", "find entry in archive", name_locate },
    { "rename", 2, "index name", "rename entry", zrename },
    { "replace_file_contents", 2, "index data", "replace entry with data", replace_file_contents },
    { "set_archive_comment", 1, "comment", "set archive comment", set_archive_comment },
    { "set_extra", 5, "index extra_id extra_index flags value", "set extra field", set_extra },
    { "set_file_comment", 2, "index comment", "set file comment", set_file_comment },
    { "set_file_compression", 3, "index method flags", "set file compression method", set_file_compression },
    { "set_file_mtime", 2, "index timestamp", "set file modification time", set_file_mtime },
    { "set_password", 1, "set default password", "set default password for encryption", set_password },
    { "stat", 1, "index", "print information about entry", zstat },
    { "unchange_all", 0, "", "revert all changes", unchange_all },
    { "zin_close", 1, "index", "close input zip_source (for internal tests)", zin_close }
};

static int
dispatch(int argc, char *argv[])
{
    unsigned int i;
    for (i=0; i<sizeof(dispatch_table)/sizeof(dispatch_table_t); i++) {
	if (strcmp(dispatch_table[i].cmdline_name, argv[0]) == 0) {
	    argc--;
	    argv++;
	    /* 1 for the command, argument_count for the arguments */
	    if (argc < dispatch_table[i].argument_count) {
		fprintf(stderr, "not enough arguments for command '%s': %d available, %d needed\n", dispatch_table[i].cmdline_name, argc, dispatch_table[i].argument_count);
		return -1;
	    }
	    if (dispatch_table[i].function(argc, argv) == 0)
		return 1 + dispatch_table[i].argument_count;
	    return -1;
	}
    }

    fprintf(stderr, "unknown command '%s'\n", argv[0]);
    return -1;
}


static void
usage(const char *progname)
{
    unsigned int i;
    fprintf(stderr, "usage: %s [-cemnt] archive command1 [args] [command2 [args] ...]\n\n"
	    "Supported options are:\n"
	    "\t-c\tcheck consistency\n"
	    "\t-e\terror if archive already exists (only useful with -n)\n"
	    "\t-g\tguess file name encoding (for stat)\n"
            "\t-H\twrite files with holes compactly\n"
	    "\t-m\tread archive into memory, and modify there; write out at end\n"
	    "\t-n\tcreate archive if it doesn't exist (default)\n"
	    "\t-r\tprint raw file name encoding without translation (for stat)\n"
	    "\t-s\tfollow file name convention strictly (for stat)\n"
	    "\t-t\tdisregard current archive contents, if any\n", progname);
    fprintf(stderr, "\nSupported commands and arguments are:\n");
    for (i=0; i<sizeof(dispatch_table)/sizeof(dispatch_table_t); i++) {
	fprintf(stderr, "\t%s %s -- %s\n", dispatch_table[i].cmdline_name, dispatch_table[i].arg_names, dispatch_table[i].description);
    }
    fprintf(stderr, "\nSupported flags are:\n"
	    "\tC\tZIP_FL_NOCASE\n"
	    "\tc\tZIP_FL_CENTRAL\n"
	    "\td\tZIP_FL_NODIR\n"
	    "\tl\tZIP_FL_LOCAL\n"
	    "\tu\tZIP_FL_UNCHANGED\n");
    fprintf(stderr, "\nThe index is zero-based.\n");
    exit(1);
}

int
main(int argc, char *argv[])
{
    const char *archive;
    zip_source_t *memory_src;
    unsigned int i;
    int c, arg, err, flags;
    const char *prg;
    source_type_t source_type = SOURCE_TYPE_NONE;

    flags = 0;
    prg = argv[0];

    if (argc < 2)
	usage(prg);

    while ((c=getopt(argc, argv, "cegHmnrst")) != -1) {
	switch (c) {
	case 'c':
	    flags |= ZIP_CHECKCONS;
	    break;
	case 'e':
	    flags |= ZIP_EXCL;
	    break;
	case 'g':
	    stat_flags = ZIP_FL_ENC_GUESS;
	    break;
        case 'H':
            source_type = SOURCE_TYPE_HOLE;
            break;
	case 'm':
            source_type = SOURCE_TYPE_IN_MEMORY;
            break;
	case 'n':
	    flags |= ZIP_CREATE;
	    break;
	case 'r':
	    stat_flags = ZIP_FL_ENC_RAW;
	    break;
	case 's':
	    stat_flags = ZIP_FL_ENC_STRICT;
	    break;
	case 't':
	    flags |= ZIP_TRUNCATE;
	    break;

	default:
	    usage(prg);
	}
    }
    
    arg = optind;

    archive = argv[arg++];

    if (flags == 0)
	flags = ZIP_CREATE;

    switch (source_type) {
        case SOURCE_TYPE_NONE:
            za = zip_open(archive, flags, &err);
            break;
            
        case SOURCE_TYPE_IN_MEMORY:
            za = read_to_memory(archive, flags, &err, &memory_src);
            break;
            
        case SOURCE_TYPE_HOLE: {
            za = read_hole(archive, flags, &err);
            break;
        }
    }
    if (za == NULL) {
	zip_error_t error;
	zip_error_init_with_code(&error, err);
	fprintf(stderr, "can't open zip archive '%s': %s\n", archive, zip_error_strerror(&error));
	zip_error_fini(&error);
	return 1;
    }

    err = 0;
    while (arg < argc) {
	int ret;
	ret = dispatch(argc-arg, argv+arg);
	if (ret > 0) {
	    arg += ret;
	} else {
	    err = 1;
	    break;
	}
    }

    if (zip_close(za) == -1) {
	fprintf(stderr, "can't close zip archive '%s': %s\n", archive, zip_strerror(za));
	return 1;
    }
    if (source_type == SOURCE_TYPE_IN_MEMORY) {
	if (write_memory_src_to_file(archive, memory_src) < 0) {
	    err = 1;
	}
	zip_source_free(memory_src);
    }

    for (i=0; i<z_in_count; i++) {
	if (zip_close(z_in[i]) < 0) {
	    err = 1;
	}
    }

    return err;
}