metalsvm/tools/make_initrd.c
2011-08-02 15:58:20 +02:00

126 lines
3.3 KiB
C

/*
* Copyright 2010 Stefan Lankes, Chair for Operating Systems,
* RWTH Aachen University
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file is part of MetalSVM.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdint.h>
#define INITRD_MAGIC_NUMBER 0x4711
#define MAX_FNAME 128
#define PAGE_SIZE 4096
typedef struct {
uint32_t magic;
uint32_t nfiles;
char mount_point[MAX_FNAME];
} initrd_header_t;
typedef struct {
uint32_t length;
uint32_t offset;
char fname[MAX_FNAME];
} initrd_file_desc_t;
static void print_options(void)
{
printf(" make_initrd mount_point path name [path name]\n");
printf("\n");
printf(" mount_point - mount point of init ram disk, where all file will be mounted.\n");
printf(" path - path to the file, which will be mounted\n");
printf(" name - file name, which will be used be the initrd\n");
}
int main(int argc, char **argv)
{
int i, nfiles = (argc - 2) / 2;
initrd_header_t header;
initrd_file_desc_t* file_desc;
off_t offset;
FILE* istream;
FILE* ostream;
if ((argc < 4) || (strcmp(argv[1], "-h") == 0)) {
print_options();
return 0;
}
memset(&header, 0x00, sizeof(initrd_header_t));
header.magic = INITRD_MAGIC_NUMBER;
header.nfiles = nfiles;
strncpy(header.mount_point, argv[1], MAX_FNAME);
file_desc = (initrd_file_desc_t*) malloc(sizeof(initrd_file_desc_t)*nfiles);
if (!file_desc) {
fprintf(stderr, "No enough memory\n");
return -1;
}
memset(file_desc, 0x00, sizeof(initrd_file_desc_t)*nfiles);
offset = sizeof(initrd_header_t) + nfiles * sizeof(initrd_file_desc_t);
for(i=0; i<nfiles; i++) {
strncpy(file_desc[i].fname, argv[3 + i * 2], MAX_FNAME);
if (offset % PAGE_SIZE)
offset += PAGE_SIZE - offset % PAGE_SIZE;
file_desc[i].offset = offset;
istream = fopen(argv[2 + i * 2], "r");
if (istream == NULL) {
fprintf(stderr, "Error: file not found: %s\n", argv[2 + i * 2]);
return -1;
}
fseek(istream, 0, SEEK_END);
file_desc[i].length = ftell(istream);
offset += file_desc[i].length;
fclose(istream);
}
ostream = fopen("./initrd.img", "w");
if (ostream == NULL) {
fprintf(stderr, "Error: unable to create file\n");
return -1;
}
fwrite(&header, sizeof(initrd_header_t), 1, ostream);
fwrite(file_desc, sizeof(initrd_file_desc_t), nfiles, ostream);
for(i=0; i<nfiles; i++) {
unsigned char *buf = (unsigned char *)malloc(file_desc[i].length);
size_t curr, len = file_desc[i].length;
istream = fopen(argv[2 + i * 2], "r");
while (ftell(ostream) < file_desc[i].offset)
fwrite(buf, 1, sizeof(unsigned char), ostream);
do {
curr = fread(buf, 1, len, istream);
fwrite(buf, 1, len, ostream);
len -= curr;
} while(len > 0);
fclose(istream);
free(buf);
}
fclose(ostream);
return 0;
}