util.c revision b5e694267142042228a6cac99ecad6c4b4ef8759
/*
* volume_id - reads filesystem label and uuid
*
* Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation version 2 of the License.
*/
#ifndef _GNU_SOURCE
#define _GNU_SOURCE 1
#endif
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include <fcntl.h>
#include <sys/stat.h>
#include "libvolume_id.h"
#include "util.h"
void volume_id_set_unicode16(char *str, size_t len, const uint8_t *buf, enum endian endianess, size_t count)
{
unsigned int i, j;
uint16_t c;
j = 0;
for (i = 0; i + 2 <= count; i += 2) {
if (endianess == LE)
c = (buf[i+1] << 8) | buf[i];
else
c = (buf[i] << 8) | buf[i+1];
if (c == 0) {
str[j] = '\0';
break;
} else if (c < 0x80) {
if (j+1 >= len)
break;
str[j++] = (uint8_t) c;
} else if (c < 0x800) {
if (j+2 >= len)
break;
str[j++] = (uint8_t) (0xc0 | (c >> 6));
str[j++] = (uint8_t) (0x80 | (c & 0x3f));
} else {
if (j+3 >= len)
break;
str[j++] = (uint8_t) (0xe0 | (c >> 12));
str[j++] = (uint8_t) (0x80 | ((c >> 6) & 0x3f));
str[j++] = (uint8_t) (0x80 | (c & 0x3f));
}
}
str[j] = '\0';
}
static char *usage_to_string(enum volume_id_usage usage_id)
{
switch (usage_id) {
case VOLUME_ID_FILESYSTEM:
return "filesystem";
case VOLUME_ID_OTHER:
return "other";
case VOLUME_ID_RAID:
return "raid";
case VOLUME_ID_DISKLABEL:
return "disklabel";
case VOLUME_ID_CRYPTO:
return "crypto";
case VOLUME_ID_UNPROBED:
return "unprobed";
case VOLUME_ID_UNUSED:
return "unused";
}
return NULL;
}
void volume_id_set_usage(struct volume_id *id, enum volume_id_usage usage_id)
{
id->usage_id = usage_id;
id->usage = usage_to_string(usage_id);
}
void volume_id_set_label_raw(struct volume_id *id, const uint8_t *buf, size_t count)
{
memcpy(id->label_raw, buf, count);
id->label_raw_len = count;
}
void volume_id_set_label_string(struct volume_id *id, const uint8_t *buf, size_t count)
{
unsigned int i;
memcpy(id->label, buf, count);
/* remove trailing whitespace */
i = strnlen(id->label, count);
while (i--) {
if (!isspace(id->label[i]))
break;
}
id->label[i+1] = '\0';
}
void volume_id_set_label_unicode16(struct volume_id *id, const uint8_t *buf, enum endian endianess, size_t count)
{
volume_id_set_unicode16(id->label, sizeof(id->label), buf, endianess, count);
}
void volume_id_set_uuid(struct volume_id *id, const uint8_t *buf, enum uuid_format format)
{
unsigned int i;
unsigned int count = 0;
switch(format) {
case UUID_DOS:
count = 4;
break;
case UUID_NTFS:
case UUID_HFS:
count = 8;
break;
case UUID_DCE:
count = 16;
break;
case UUID_DCE_STRING:
count = 36;
break;
}
memcpy(id->uuid_raw, buf, count);
id->uuid_raw_len = count;
/* if set, create string in the same format, the native platform uses */
for (i = 0; i < count; i++)
if (buf[i] != 0)
goto set;
return;
set:
switch(format) {
case UUID_DOS:
sprintf(id->uuid, "%02X%02X-%02X%02X",
buf[3], buf[2], buf[1], buf[0]);
break;
case UUID_NTFS:
sprintf(id->uuid,"%02X%02X%02X%02X%02X%02X%02X%02X",
buf[7], buf[6], buf[5], buf[4],
buf[3], buf[2], buf[1], buf[0]);
break;
case UUID_HFS:
sprintf(id->uuid,"%02X%02X%02X%02X%02X%02X%02X%02X",
buf[0], buf[1], buf[2], buf[3],
buf[4], buf[5], buf[6], buf[7]);
break;
case UUID_DCE:
sprintf(id->uuid,
"%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
buf[0], buf[1], buf[2], buf[3],
buf[4], buf[5],
buf[6], buf[7],
buf[8], buf[9],
buf[10], buf[11], buf[12], buf[13], buf[14],buf[15]);
break;
case UUID_DCE_STRING:
memcpy(id->uuid, buf, count);
id->uuid[count] = '\0';
break;
}
}
uint8_t *volume_id_get_buffer(struct volume_id *id, uint64_t off, size_t len)
{
ssize_t buf_len;
dbg("get buffer off 0x%llx(%llu), len 0x%zx", (unsigned long long) off, (unsigned long long) off, len);
/* check if requested area fits in superblock buffer */
if (off + len <= SB_BUFFER_SIZE) {
if (id->sbbuf == NULL) {
id->sbbuf = malloc(SB_BUFFER_SIZE);
if (id->sbbuf == NULL) {
dbg("error malloc");
return NULL;
}
}
/* check if we need to read */
if ((off + len) > id->sbbuf_len) {
dbg("read sbbuf len:0x%llx", (unsigned long long) (off + len));
if (lseek(id->fd, 0, SEEK_SET) < 0) {
dbg("lseek failed (%s)", strerror(errno));
return NULL;
}
buf_len = read(id->fd, id->sbbuf, off + len);
if (buf_len < 0) {
dbg("read failed (%s)", strerror(errno));
return NULL;
}
dbg("got 0x%zx (%zi) bytes", buf_len, buf_len);
id->sbbuf_len = buf_len;
if ((size_t)buf_len < off + len) {
dbg("requested 0x%zx bytes, got only 0x%zx bytes", len, buf_len);
return NULL;
}
}
return &(id->sbbuf[off]);
} else {
if (len > SEEK_BUFFER_SIZE) {
dbg("seek buffer too small %d", SEEK_BUFFER_SIZE);
return NULL;
}
/* get seek buffer */
if (id->seekbuf == NULL) {
id->seekbuf = malloc(SEEK_BUFFER_SIZE);
if (id->seekbuf == NULL) {
dbg("error malloc");
return NULL;
}
}
/* check if we need to read */
if ((off < id->seekbuf_off) || ((off + len) > (id->seekbuf_off + id->seekbuf_len))) {
dbg("read seekbuf off:0x%llx len:0x%zx", (unsigned long long) off, len);
if (lseek(id->fd, off, SEEK_SET) < 0) {
dbg("lseek failed (%s)", strerror(errno));
return NULL;
}
buf_len = read(id->fd, id->seekbuf, len);
if (buf_len < 0) {
dbg("read failed (%s)", strerror(errno));
return NULL;
}
dbg("got 0x%zx (%zi) bytes", buf_len, buf_len);
id->seekbuf_off = off;
id->seekbuf_len = buf_len;
if ((size_t)buf_len < len) {
dbg("requested 0x%zx bytes, got only 0x%zx bytes", len, buf_len);
return NULL;
}
}
return &(id->seekbuf[off - id->seekbuf_off]);
}
}
void volume_id_free_buffer(struct volume_id *id)
{
if (id->sbbuf != NULL) {
free(id->sbbuf);
id->sbbuf = NULL;
id->sbbuf_len = 0;
}
if (id->seekbuf != NULL) {
free(id->seekbuf);
id->seekbuf = NULL;
id->seekbuf_len = 0;
}
}