Add a tool to extract pakfiles

This commit is contained in:
Yamagi Burmeister 2012-04-04 15:30:26 +00:00
commit 5e70aa132e
3 changed files with 333 additions and 0 deletions

42
Makefile Normal file
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# The compiler
CC := gcc
# ----------
# Base CFLAGS
CFLAGS := -O2 -Wall -ansi -pedantic
# ----------
# When make is invoked by "make VERBOSE=1" print
# the compiler and linker commands.
ifdef VERBOSE
Q :=
else
Q := @
endif
# ----------
# The converter rule
%.o: %.c
@echo '===> CC $<'
${Q}$(CC) -c $(CFLAGS) -o $@ $<
# ----------
PAK_OBJS = \
pakextract.o
# ----------
pakextract: $(PAK_OBJS)
@echo '===> LD $@'
${Q}$(CC) $(PAK_OBJS) -o $@
# ----------
clean:
@echo "===> CLEAN"
${Q}rm -Rf pakextract.o pakextract

42
README Normal file
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pakextract
----------
pakextract is a small tool to extract the contents of
a Quake II pak file into the current directory. Usage:
./pakextract /path/to/pakfile.pak
Only Quake II paks are supported. Other pak formats may
work but it's untested and unsupported.
-------------------------------------------------------
The Quake II Pak File Format
----------------------------
A Quake II pak file consists of 3 parts:
- Header
- Directory
- Data
The header is written right after the start
of the file and consists of 3 parts in the
following order:
- A 4 byte identification string "PACK" (in ASCII)
- A 4 byte integer value defining the offset to the
directory in bytes
- A 4 byte iteger giving the length of the directory
in bytes. Since every directory entry is 64 bytes
long this value modulo 64 must be 0:
(dir_length % 64) == 0;
The directory can be anywere in the file but most times
it's written to the end. In consists of datablocks,
written one after the other without any space between
them. A directory entry is 64 bytes long has entries
in the following order:
- A 56 byte file name (in ASCII)
- A 4 byte value defining the position if the file
as an offset in bytes to the start of the pak file.
- A 4 byte integer giving the length of the file
in bytes.

249
pakextract.c Normal file
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/*-
* Copyright (c) 2012 Yamagi Burmeister
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
/* Holds the pak header */
struct
{
char signature[4];
int dir_offset;
int dir_length;
} header;
/* A directory entry */
struct directory_s
{
char file_name[56];
int file_pos;
int file_length;
struct directory_s *next;
};
typedef struct directory_s directory;
/*
* Creates a directory tree.
*
* *s -> The path to create. The last
* part (the file itself) is
* ommitted
*/
void
mktree(char *s)
{
char *dir;
char *elements[28];
char *path;
char *token;
int i, j;
path = calloc(56, sizeof(char));
dir = malloc(sizeof(char) * 56);
strncpy(dir, s, sizeof(char) * 56);
for (i = 0; (token = strsep(&dir, "/")) != NULL; i++)
{
elements[i] = token;
}
for (j = 0; j < i - 1; j++)
{
strcat(path, elements[j]);
strcat(path, "/");
mkdir(path, 0700);
}
free(path);
free(dir);
}
/*
* Reads the pak file header and
* stores it into the global struct
* "header".
*
* *fd -> A file descriptor holding
* the pack to be read.
*/
int
read_header(FILE *fd)
{
if (fread(&header, sizeof(header), 1, fd) != 1)
{
perror("Could not read the pak file header");
return -1;
}
if (strncmp(header.signature, "PACK", 4))
{
fprintf(stderr, "Not a pak file\n");
return -1;
}
if ((header.dir_length % 64) != 0)
{
fprintf(stderr, "Corrupt pak file\n");
return -1;
}
return 0;
}
/*
* Reads the directory of a pak file
* into a linked list and returns
* a pointer to the first element.
*
* *fd -> a file descriptor holding
* holding the pak to be read
*/
directory *
read_directory(FILE *fd)
{
int i;
directory *head, *cur;
head = NULL;
/* Navigate to the directory */
fseek(fd, header.dir_offset, SEEK_SET);
for (i = 0; i < (header.dir_length / 64); i++)
{
cur = malloc(sizeof(directory));
if (fread(cur, sizeof(directory) - sizeof(directory *), 1, fd) != 1)
{
perror("Could not read directory entry");
return NULL;
}
cur->next = head;
head = cur;
}
return head;
}
/*
* Extract the files from a pak.
*
* *d -> a pointer to the first element
* of the pak directory
*
* *fd -> a file descriptor holding
* the pak to be extracted
*/
void
extract_files(FILE *fd, directory *d)
{
char b;
directory *old_d;
FILE *out;
int i;
while (d != NULL)
{
mktree(d->file_name);
out = fopen(d->file_name, "w");
if (out == NULL)
{
perror("Could open the outputfile");
return;
}
fseek(fd, d->file_pos, SEEK_SET);
for (i = 0; i < d->file_length; i++)
{
fread(&b, sizeof(char), 1, fd);
fwrite(&b, sizeof(char), 1, out);
}
fclose(out);
old_d = d;
d = d->next;
free(old_d);
}
}
/*
* A small programm to extract a Quake II pak file.
* The pak file is given as the first an only
* argument.
*/
int
main(int argc, char *argv[])
{
directory *d;
FILE *fd;
/* Correct usage? */
if (argc != 2)
{
fprintf(stderr, "Usage: %s pakfile\n", argv[0]);
exit(-1);
}
/* Open the pak file */
fd = fopen(argv[1], "r");
if (fd == NULL)
{
perror("Could not open the pak file");
exit(-1);
}
/* Read the header */
if (read_header(fd) < 0)
{
fclose(fd);
exit(-1);
}
/* Read the directory */
d = read_directory(fd);
if (d == NULL)
{
fclose(fd);
exit(-1);
}
/* And now extract the files */
extract_files(fd, d);
/* cleanup */
fclose(fd);
return 0;
}