NetBSD/dist/pdisk/dump.c
he e437fa175c Now that we have strnlen() in libc, get rid of the local
and type-conflicting implementation here instead of fixing
it locally.  I don't think (hope!) this is size-critical.
2009-05-10 22:03:22 +00:00

906 lines
22 KiB
C

//
// dump.c - dumping partition maps
//
// Written by Eryk Vershen
//
/*
* Copyright 1996,1997,1998 by Apple Computer, Inc.
* All Rights Reserved
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appears in all copies and
* that both the copyright notice and this permission notice appear in
* supporting documentation.
*
* APPLE COMPUTER DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE.
*
* IN NO EVENT SHALL APPLE COMPUTER BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
* NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
* WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
// for *printf()
#include <stdio.h>
// for malloc() & free()
#ifndef __linux__
#include <stdlib.h>
//#include <unistd.h>
#else
#include <malloc.h>
#endif
// for strcmp()
#include <string.h>
// for O_RDONLY
#include <fcntl.h>
// for errno
#include <errno.h>
#include "dump.h"
#include "pathname.h"
#include "io.h"
#include "errors.h"
//
// Defines
//
#if DPISTRLEN != 32
#error Change in strlen in partition entries! Fix constants
#endif
#define get_align_long(x) (*(x))
//
// Types
//
typedef struct names {
const char *abbr;
const char *full;
} NAMES;
#ifdef __unix__
typedef unsigned long OSType;
#endif
typedef struct PatchDescriptor {
OSType patchSig;
unsigned short majorVers;
unsigned short minorVers;
unsigned long flags;
unsigned long patchOffset;
unsigned long patchSize;
unsigned long patchCRC;
unsigned long patchDescriptorLen;
unsigned char patchName[33];
unsigned char patchVendor[1];
} PatchDescriptor;
typedef PatchDescriptor * PatchDescriptorPtr;
typedef struct PatchList {
unsigned short numPatchBlocks; // number of disk blocks to hold the patch list
unsigned short numPatches; // number of patches in list
PatchDescriptor thePatch[1];
} PatchList;
typedef PatchList *PatchListPtr;
//
// Global Constants
//
NAMES plist[] = {
{"Drvr", "Apple_Driver"},
{"Drv4", "Apple_Driver43"},
{"Free", "Apple_Free"},
{"Patc", "Apple_Patches"},
{" HFS", "Apple_HFS"},
{" MFS", "Apple_MFS"},
{"PDOS", "Apple_PRODOS"},
{"junk", "Apple_Scratch"},
{"unix", "Apple_UNIX_SVR2"},
{" map", "Apple_partition_map"},
{0, 0},
};
const char * kStringEmpty = "";
const char * kStringNot = " not";
//
// Global Variables
//
int aflag = AFLAG_DEFAULT; /* abbreviate partition types */
int pflag = PFLAG_DEFAULT; /* show physical limits of partition */
int fflag = FFLAG_DEFAULT; /* show HFS volume names */
//
// Forward declarations
//
void adjust_value_and_compute_prefix(double *value, int *prefix);
void dump_block_zero(partition_map_header *map);
void dump_partition_entry(partition_map *entry, int type_length, int name_length, int digits);
int get_max_base_or_length(partition_map_header *map);
int get_max_name_string_length(partition_map_header *map);
int get_max_type_string_length(partition_map_header *map);
//
// Routines
//
int
dump(char *name)
{
partition_map_header *map;
int junk;
map = open_partition_map(name, &junk, 0);
if (map == NULL) {
//error(-1, "No partition map in '%s'", name);
return 0;
}
dump_partition_map(map, 1);
close_partition_map(map);
return 1;
}
void
dump_block_zero(partition_map_header *map)
{
Block0 *p;
DDMap *m;
int i;
double value;
int prefix;
long t;
p = map->misc;
if (p->sbSig != BLOCK0_SIGNATURE) {
return;
}
value = ((double)p->sbBlkCount) * p->sbBlkSize;
adjust_value_and_compute_prefix(&value, &prefix);
printf("\nDevice block size=%u, Number of Blocks=%lu (%1.1f%c)\n",
p->sbBlkSize, p->sbBlkCount, value, prefix);
printf("DeviceType=0x%x, DeviceId=0x%x\n",
p->sbDevType, p->sbDevId);
if (p->sbDrvrCount > 0) {
printf("Drivers-\n");
m = (DDMap *) p->sbMap;
for (i = 0; i < p->sbDrvrCount; i++) {
printf("%u: %3u @ %lu, ", i+1,
m[i].ddSize, get_align_long(&m[i].ddBlock));
if (map->logical_block != p->sbBlkSize) {
t = (m[i].ddSize * p->sbBlkSize) / map->logical_block;
printf("(%lu@", t);
t = (get_align_long(&m[i].ddBlock) * p->sbBlkSize)
/ map->logical_block;
printf("%lu) ", t);
}
printf("type=0x%x\n", m[i].ddType);
}
}
printf("\n");
}
void
dump_partition_map(partition_map_header *map, int disk_order)
{
partition_map * entry;
int max_type_length;
int max_name_length;
int digits;
char *alternate;
if (map == NULL) {
bad_input("No partition map exists");
return;
}
alternate = get_linux_name(map->name);
if (alternate) {
printf("\nPartition map (with %d byte blocks) on '%s' (%s)\n",
map->logical_block, map->name, alternate);
free(alternate);
} else {
printf("\nPartition map (with %d byte blocks) on '%s'\n",
map->logical_block, map->name);
}
digits = number_of_digits(get_max_base_or_length(map));
if (digits < 6) {
digits = 6;
}
if (aflag) {
max_type_length = 4;
} else {
max_type_length = get_max_type_string_length(map);
if (max_type_length < 4) {
max_type_length = 4;
}
}
max_name_length = get_max_name_string_length(map);
if (max_name_length < 6) {
max_name_length = 6;
}
printf(" #: %*s %-*s %*s %-*s ( size )\n",
max_type_length, "type",
max_name_length, "name",
digits, "length", digits, "base");
if (disk_order) {
for (entry = map->disk_order; entry != NULL;
entry = entry->next_on_disk) {
dump_partition_entry(entry, max_type_length, max_name_length, digits);
}
} else {
for (entry = map->base_order; entry != NULL;
entry = entry->next_by_base) {
dump_partition_entry(entry, max_type_length, max_name_length, digits);
}
}
dump_block_zero(map);
}
void
dump_partition_entry(partition_map *entry, int type_length, int name_length, int digits)
{
partition_map_header *map;
int j;
DPME *p;
const char *s;
u32 size;
double bytes;
int driver;
// int kind;
char *buf;
#if 1
BZB *bp;
#endif
map = entry->the_map;
p = entry->data;
driver = entry->contains_driver? '*': ' ';
if (aflag) {
s = "????";
for (j = 0; plist[j].abbr != 0; j++) {
if (strcmp(p->dpme_type, plist[j].full) == 0) {
s = plist[j].abbr;
break;
}
}
printf("%2ld: %.4s", entry->disk_address, s);
} else {
printf("%2ld: %*.32s", entry->disk_address, type_length, p->dpme_type);
}
buf = (char *) malloc(name_length+1);
if (entry->HFS_name == NULL || fflag == 0) {
strncpy(buf, p->dpme_name, name_length);
buf[name_length] = 0;
} else {
snprintf(buf, name_length + 1, "\"%s\"", entry->HFS_name);
}
printf("%c%-*.32s ", driver, name_length, buf);
free(buf);
/*
switch (entry->HFS_kind) {
case kHFS_std: kind = 'h'; break;
case kHFS_embed: kind = 'e'; break;
case kHFS_plus: kind = '+'; break;
default:
case kHFS_not: kind = ' '; break;
}
printf("%c ", kind);
*/
if (pflag) {
printf("%*lu ", digits, p->dpme_pblocks);
size = p->dpme_pblocks;
} else if (p->dpme_lblocks + p->dpme_lblock_start != p->dpme_pblocks) {
printf("%*lu+", digits, p->dpme_lblocks);
size = p->dpme_lblocks;
} else if (p->dpme_lblock_start != 0) {
printf("%*lu ", digits, p->dpme_lblocks);
size = p->dpme_lblocks;
} else {
printf("%*lu ", digits, p->dpme_pblocks);
size = p->dpme_pblocks;
}
if (pflag || p->dpme_lblock_start == 0) {
printf("@ %-*lu", digits, p->dpme_pblock_start);
} else {
printf("@~%-*lu", digits, p->dpme_pblock_start + p->dpme_lblock_start);
}
bytes = ((double)size) * map->logical_block;
adjust_value_and_compute_prefix(&bytes, &j);
if (j != ' ' && j != 'K') {
printf(" (%#5.1f%c)", bytes, j);
}
#if 1
// Old A/UX fields that no one pays attention to anymore.
bp = (BZB *) (p->dpme_bzb);
j = -1;
if (bp->bzb_magic == BZBMAGIC) {
switch (bp->bzb_type) {
case FSTEFS:
s = "EFS";
break;
case FSTSFS:
s = "SFS";
j = 1;
break;
case FST:
default:
if (bzb_root_get(bp) != 0) {
if (bzb_usr_get(bp) != 0) {
s = "RUFS";
} else {
s = "RFS";
}
j = 0;
} else if (bzb_usr_get(bp) != 0) {
s = "UFS";
j = 2;
} else {
s = "FS";
}
break;
}
if (bzb_slice_get(bp) != 0) {
printf(" s%1ld %4s", bzb_slice_get(bp)-1, s);
} else if (j >= 0) {
printf(" S%1d %4s", j, s);
} else {
printf(" %4s", s);
}
if (bzb_crit_get(bp) != 0) {
printf(" K%1d", bp->bzb_cluster);
} else if (j < 0) {
printf(" ");
} else {
printf(" k%1d", bp->bzb_cluster);
}
if (bp->bzb_mount_point[0] != 0) {
printf(" %.64s", bp->bzb_mount_point);
}
}
#endif
printf("\n");
}
void
list_all_disks()
{
MEDIA_ITERATOR iter;
MEDIA m;
DPME * data;
char *name;
long mark;
data = (DPME *) malloc(PBLOCK_SIZE);
if (data == NULL) {
error(errno, "can't allocate memory for try buffer");
return;
}
for (iter = first_media_kind(&mark); iter != 0; iter = next_media_kind(&mark)) {
while ((name = step_media_iterator(iter)) != 0) {
if ((m = open_pathname_as_media(name, O_RDONLY)) == 0) {
#if defined(__linux__) || defined(__unix__)
error(errno, "can't open file '%s'", name);
#endif
} else {
close_media(m);
dump(name);
}
free(name);
}
delete_media_iterator(iter);
}
free(data);
}
void
show_data_structures(partition_map_header *map)
{
Block0 *zp;
DDMap *m;
int i;
int j;
partition_map * entry;
DPME *p;
BZB *bp;
const char *s;
if (map == NULL) {
printf("No partition map exists\n");
return;
}
printf("Header:\n");
printf("map %d blocks out of %d, media %lu blocks (%d byte blocks)\n",
map->blocks_in_map, map->maximum_in_map,
map->media_size, map->logical_block);
printf("Map is%s writable", (map->writable)?kStringEmpty:kStringNot);
printf(", but%s changed", (map->changed)?kStringEmpty:kStringNot);
printf(" and has%s been written\n", (map->written)?kStringEmpty:kStringNot);
printf("\n");
if (map->misc == NULL) {
printf("No block zero\n");
} else {
zp = map->misc;
printf("Block0:\n");
printf("signature 0x%x", zp->sbSig);
if (zp->sbSig == BLOCK0_SIGNATURE) {
printf("\n");
} else {
printf(" should be 0x%x\n", BLOCK0_SIGNATURE);
}
printf("Block size=%u, Number of Blocks=%lu\n",
zp->sbBlkSize, zp->sbBlkCount);
printf("DeviceType=0x%x, DeviceId=0x%x, sbData=0x%lx\n",
zp->sbDevType, zp->sbDevId, zp->sbData);
if (zp->sbDrvrCount == 0) {
printf("No drivers\n");
} else {
printf("%u driver%s-\n", zp->sbDrvrCount,
(zp->sbDrvrCount>1)?"s":kStringEmpty);
m = (DDMap *) zp->sbMap;
for (i = 0; i < zp->sbDrvrCount; i++) {
printf("%u: @ %lu for %u, type=0x%x\n", i+1,
get_align_long(&m[i].ddBlock),
m[i].ddSize, m[i].ddType);
}
}
}
printf("\n");
/*
u32 dpme_boot_args[32] ;
u32 dpme_reserved_3[62] ;
*/
printf(" #: type length base "
"flags (logical)\n");
for (entry = map->disk_order; entry != NULL; entry = entry->next_on_disk) {
p = entry->data;
printf("%2ld: %20.32s ",
entry->disk_address, p->dpme_type);
printf("%7lu @ %-7lu ", p->dpme_pblocks, p->dpme_pblock_start);
printf("%c%c%c%c%c%c%c%c%c%c%c%c ",
(dpme_valid_get(p))?'V':'.',
(dpme_allocated_get(p))?'A':'.',
(dpme_in_use_get(p))?'I':'.',
(dpme_bootable_get(p))?'B':'.',
(dpme_readable_get(p))?'R':'.',
(dpme_writable_get(p))?'W':'.',
(dpme_os_pic_code_get(p))?'P':'.',
(dpme_os_specific_2_get(p))?'2':'.',
(dpme_chainable_get(p))?'C':'.',
(dpme_diskdriver_get(p))?'D':'.',
(bitfield_get(p->dpme_flags, 30, 1))?'M':'.',
(bitfield_get(p->dpme_flags, 31, 1))?'X':'.');
if (p->dpme_lblock_start != 0 || p->dpme_pblocks != p->dpme_lblocks) {
printf("(%lu @ %lu)", p->dpme_lblocks, p->dpme_lblock_start);
}
printf("\n");
}
printf("\n");
printf(" #: booter bytes load_address "
"goto_address checksum processor\n");
for (entry = map->disk_order; entry != NULL; entry = entry->next_on_disk) {
p = entry->data;
printf("%2ld: ", entry->disk_address);
printf("%7lu ", p->dpme_boot_block);
printf("%7lu ", p->dpme_boot_bytes);
printf("%8lx ", (u32)p->dpme_load_addr);
printf("%8lx ", (u32)p->dpme_load_addr_2);
printf("%8lx ", (u32)p->dpme_goto_addr);
printf("%8lx ", (u32)p->dpme_goto_addr_2);
printf("%8lx ", p->dpme_checksum);
printf("%.32s", p->dpme_process_id);
printf("\n");
}
printf("\n");
/*
xx: cccc RU *dd s...
*/
printf(" #: type RU *slice mount_point (A/UX only fields)\n");
for (entry = map->disk_order; entry != NULL; entry = entry->next_on_disk) {
p = entry->data;
printf("%2ld: ", entry->disk_address);
bp = (BZB *) (p->dpme_bzb);
j = -1;
if (bp->bzb_magic == BZBMAGIC) {
switch (bp->bzb_type) {
case FSTEFS:
s = "esch";
break;
case FSTSFS:
s = "swap";
j = 1;
break;
case FST:
default:
s = "fsys";
if (bzb_root_get(bp) != 0) {
j = 0;
} else if (bzb_usr_get(bp) != 0) {
j = 2;
}
break;
}
printf("%4s ", s);
printf("%c%c ",
(bzb_root_get(bp))?'R':' ',
(bzb_usr_get(bp))?'U':' ');
if (bzb_slice_get(bp) != 0) {
printf(" %2ld", bzb_slice_get(bp)-1);
} else if (j >= 0) {
printf(" *%2d", j);
} else {
printf(" ");
}
if (bp->bzb_mount_point[0] != 0) {
printf(" %.64s", bp->bzb_mount_point);
}
}
printf("\n");
}
}
void
full_dump_partition_entry(partition_map_header *map, int ix)
{
partition_map * cur;
DPME *p;
int i;
u32 t;
cur = find_entry_by_disk_address(ix, map);
if (cur == NULL) {
printf("No such partition\n");
return;
}
p = cur->data;
printf(" signature: 0x%x\n", p->dpme_signature);
printf(" reserved1: 0x%x\n", p->dpme_reserved_1);
printf(" number of map entries: %ld\n", p->dpme_map_entries);
printf(" physical start: %10lu length: %10lu\n", p->dpme_pblock_start, p->dpme_pblocks);
printf(" logical start: %10lu length: %10lu\n", p->dpme_lblock_start, p->dpme_lblocks);
printf(" flags: 0x%lx\n", (u32)p->dpme_flags);
printf(" ");
if (dpme_valid_get(p)) printf("valid ");
if (dpme_allocated_get(p)) printf("alloc ");
if (dpme_in_use_get(p)) printf("in-use ");
if (dpme_bootable_get(p)) printf("boot ");
if (dpme_readable_get(p)) printf("read ");
if (dpme_writable_get(p)) printf("write ");
if (dpme_os_pic_code_get(p)) printf("pic ");
t = p->dpme_flags >> 7;
for (i = 7; i <= 31; i++) {
if (t & 0x1) {
printf("%d ", i);
}
t = t >> 1;
}
printf("\n");
printf(" name: '%.32s'\n", p->dpme_name);
printf(" type: '%.32s'\n", p->dpme_type);
printf(" boot start block: %10lu\n", p->dpme_boot_block);
printf("boot length (in bytes): %10lu\n", p->dpme_boot_bytes);
printf(" load address: 0x%08lx 0x%08lx\n",
(u32)p->dpme_load_addr, (u32)p->dpme_load_addr_2);
printf(" start address: 0x%08lx 0x%08lx\n",
(u32)p->dpme_goto_addr, (u32)p->dpme_goto_addr_2);
printf(" checksum: 0x%08lx\n", p->dpme_checksum);
printf(" processor: '%.32s'\n", p->dpme_process_id);
printf("boot args field -");
dump_block((unsigned char *)p->dpme_boot_args, 32*4);
printf("dpme_reserved_3 -");
dump_block((unsigned char *)p->dpme_reserved_3, 62*4);
}
void
dump_block(unsigned char *addr, int len)
{
int i;
int j;
int limit1;
int limit;
#define LINE_LEN 16
#define UNIT_LEN 4
#define OTHER_LEN 8
for (i = 0; i < len; i = limit) {
limit1 = i + LINE_LEN;
if (limit1 > len) {
limit = len;
} else {
limit = limit1;
}
printf("\n%03x: ", i);
for (j = i; j < limit1; j++) {
if (j % UNIT_LEN == 0) {
printf(" ");
}
if (j < limit) {
printf("%02x", addr[j]);
} else {
printf(" ");
}
}
printf(" ");
for (j = i; j < limit; j++) {
if (j % OTHER_LEN == 0) {
printf(" ");
}
if (addr[j] < ' ') {
printf(".");
} else {
printf("%c", addr[j]);
}
}
}
printf("\n");
}
void
full_dump_block_zero(partition_map_header *map)
{
Block0 *zp;
DDMap *m;
int i;
if (map == NULL) {
printf("No partition map exists\n");
return;
}
if (map->misc == NULL) {
printf("No block zero\n");
return;
}
zp = map->misc;
printf(" signature: 0x%x\n", zp->sbSig);
printf(" size of a block: %d\n", zp->sbBlkSize);
printf(" number of blocks: %ld\n", zp->sbBlkCount);
printf(" device type: 0x%x\n", zp->sbDevType);
printf(" device id: 0x%x\n", zp->sbDevId);
printf(" data: 0x%lx\n", zp->sbData);
printf(" driver count: %d\n", zp->sbDrvrCount);
m = (DDMap *) zp->sbMap;
for (i = 0; &m[i].ddType < &zp->sbMap[247]; i++) {
if (m[i].ddBlock == 0 && m[i].ddSize == 0 && m[i].ddType == 0) {
break;
}
printf(" driver %3u block: %ld\n", i+1, m[i].ddBlock);
printf(" size in blocks: %d\n", m[i].ddSize);
printf(" driver type: 0x%x\n", m[i].ddType);
}
printf("remainder of block -");
dump_block((unsigned char *)(void *)&m[i].ddBlock, (&zp->sbMap[247]-((unsigned short *)(void *)&m[i].ddBlock))*2);
}
void
display_patches(partition_map *entry)
{
long long offset;
MEDIA m;
static unsigned char *patch_block;
PatchListPtr p;
PatchDescriptorPtr q;
unsigned char *next;
unsigned char *s;
int i;
offset = entry->data->dpme_pblock_start;
m = entry->the_map->m;
offset = ((long long) entry->data->dpme_pblock_start) * entry->the_map->logical_block;
if (patch_block == NULL) {
patch_block = (unsigned char *) malloc(PBLOCK_SIZE);
if (patch_block == NULL) {
error(errno, "can't allocate memory for patch block buffer");
return;
}
}
if (read_media(m, (long long)offset, PBLOCK_SIZE, (char *)patch_block) == 0) {
error(errno, "Can't read patch block");
return;
}
p = (PatchListPtr) patch_block;
if (p->numPatchBlocks != 1) {
i = p->numPatchBlocks;
free(patch_block);
patch_block = (unsigned char *) malloc(PBLOCK_SIZE*i);
if (patch_block == NULL) {
error(errno, "can't allocate memory for patch blocks buffer");
return;
}
s = patch_block + PBLOCK_SIZE*i;
while (i > 0) {
s -= PBLOCK_SIZE;
i -= 1;
if (read_media(m, offset+i, PBLOCK_SIZE, (char *)s) == 0) {
error(errno, "Can't read patch block %d", i);
return;
}
}
p = (PatchListPtr) patch_block;
}
printf("Patch list (%d entries)\n", p->numPatches);
q = p->thePatch;
for (i = 0; i < p->numPatches; i++) {
printf("%2d signature: '%.4s'\n", i+1, (char *)&q->patchSig);
printf(" version: %d.%d\n", q->majorVers, q->minorVers);
printf(" flags: 0x%lx\n", q->flags);
printf(" offset: %ld\n", q->patchOffset);
printf(" size: %ld\n", q->patchSize);
printf(" CRC: 0x%lx\n", q->patchCRC);
printf(" name: '%.*s'\n", q->patchName[0], &q->patchName[1]);
printf(" vendor: '%.*s'\n", q->patchVendor[0], &q->patchVendor[1]);
next = ((unsigned char *)q) + q->patchDescriptorLen;
s = &q->patchVendor[q->patchVendor[0]+1];
if (next > s) {
printf("remainder of entry -");
dump_block(s, next-s);
}
q = (PatchDescriptorPtr)next;
}
}
int
get_max_type_string_length(partition_map_header *map)
{
partition_map * entry;
int max;
int length;
if (map == NULL) {
return 0;
}
max = 0;
for (entry = map->disk_order; entry != NULL; entry = entry->next_on_disk) {
length = strnlen(entry->data->dpme_type, DPISTRLEN);
if (length > max) {
max = length;
}
}
return max;
}
int
get_max_name_string_length(partition_map_header *map)
{
partition_map * entry;
int max;
int length;
if (map == NULL) {
return 0;
}
max = 0;
for (entry = map->disk_order; entry != NULL; entry = entry->next_on_disk) {
length = strnlen(entry->data->dpme_name, DPISTRLEN);
if (length > max) {
max = length;
}
if (fflag) {
if (entry->HFS_name == NULL) {
length = 0;
} else {
length = strlen(entry->HFS_name) + 2;
}
if (length > max) {
max = length;
}
}
}
return max;
}
int
get_max_base_or_length(partition_map_header *map)
{
partition_map * entry;
unsigned int max;
if (map == NULL) {
return 0;
}
max = 0;
for (entry = map->disk_order; entry != NULL; entry = entry->next_on_disk) {
if (entry->data->dpme_pblock_start > max) {
max = entry->data->dpme_pblock_start;
}
if (entry->data->dpme_pblocks > max) {
max = entry->data->dpme_pblocks;
}
if (entry->data->dpme_lblock_start > max) {
max = entry->data->dpme_lblock_start;
}
if (entry->data->dpme_lblocks > max) {
max = entry->data->dpme_lblocks;
}
}
return max;
}
void
adjust_value_and_compute_prefix(double *value, int *prefix)
{
double bytes;
int multiplier;
bytes = *value;
if (bytes < 1024.0) {
multiplier = ' ';
} else {
bytes = bytes / 1024.0;
if (bytes < 1024.0) {
multiplier = 'K';
} else {
bytes = bytes / 1024.0;
if (bytes < 1024.0) {
multiplier = 'M';
} else {
bytes = bytes / 1024.0;
if (bytes < 1024.0) {
multiplier = 'G';
} else {
bytes = bytes / 1024.0;
multiplier = 'T';
}
}
}
}
*value = bytes;
*prefix = multiplier;
}