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/*
* partitions - partition tables parsing
*
* Copyright (C) 2008-2009 Karel Zak <kzak@redhat.com>
*
* This file may be redistributed under the terms of the
* GNU Lesser General Public License.
*
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdarg.h>
#include "partitions.h"
#include "sysfs.h"
/**
* SECTION: partitions
* @title: Partitions probing
* @short_description: partitions tables detection and parsing
*
* This chain supports binary and NAME=value interfaces, but complete PT
* description is provided by binary interface only. The libblkid prober is
* compatible with kernel partition tables parser. The parser does not return
* empty (size=0) partitions or special hidden partitions.
*
* NAME=value interface, supported tags:
*
* @PTTYPE: partition table type (dos, gpt, etc.).
*
* @PART_ENTRY_SCHEME: partition table type
*
* @PART_ENTRY_NAME: partition name (gpt and mac only)
*
* @PART_ENTRY_UUID: partition UUID (gpt only)
*
* @PART_ENTRY_TYPE: partition type, 0xNN (e.g 0x82) or type UUID (gpt only) or type string (mac)
*
* @PART_ENTRY_FLAGS: partition flags (e.g. boot_ind) or attributes (e.g. gpt attributes)
*
* @PART_ENTRY_NUMBER: partition number
*
* @PART_ENTRY_OFFSET: the begin of the partition
*
* @PART_ENTRY_SIZE: size of the partition
*
* @PART_ENTRY_DISK: whole-disk maj:min
*
* Example:
*
* <informalexample>
* <programlisting>
* blkid_probe pr;
* const char *ptname;
*
* pr = blkid_new_probe_from_filename(devname);
* if (!pr)
* err("%s: faild to open device", devname);
*
* blkid_probe_enable_partitions(pr, TRUE);
* blkid_do_fullprobe(pr);
*
* blkid_probe_lookup_value(pr, "PTTYPE", &ptname, NULL);
* printf("%s partition type detected\n", pttype);
*
* blkid_free_probe(pr);
*
* // don't forget to check return codes in your code!
* </programlisting>
* </informalexample>
*
* Binary interface:
*
* <informalexample>
* <programlisting>
* blkid_probe pr;
* blkid_partlist ls;
* int nparts, i;
*
* pr = blkid_new_probe_from_filename(devname);
* if (!pr)
* err("%s: faild to open device", devname);
*
* ls = blkid_probe_get_partitions(pr);
* nparts = blkid_partlist_numof_partitions(ls);
*
* for (i = 0; i < nparts; i++) {
* blkid_partition par = blkid_partlist_get_partition(ls, i);
* printf("#%d: %llu %llu 0x%x",
* blkid_partition_get_partno(par),
* blkid_partition_get_start(par),
* blkid_partition_get_size(par),
* blkid_partition_get_type(par));
* }
*
* blkid_free_probe(pr);
*
* // don't forget to check return codes in your code!
* </programlisting>
* </informalexample>
*/
/*
* Chain driver function
*/
static int partitions_probe(blkid_probe pr, struct blkid_chain *chn);
static void partitions_free_data(blkid_probe pr, void *data);
/*
* Partitions chain probing functions
*/
static const struct blkid_idinfo *idinfos[] =
{
&aix_pt_idinfo,
&sgi_pt_idinfo,
&sun_pt_idinfo,
&dos_pt_idinfo,
&gpt_pt_idinfo,
&mac_pt_idinfo,
&ultrix_pt_idinfo,
&bsd_pt_idinfo,
&unixware_pt_idinfo,
&solaris_x86_pt_idinfo,
&minix_pt_idinfo
};
/*
* Driver definition
*/
const struct blkid_chaindrv partitions_drv = {
.id = BLKID_CHAIN_PARTS,
.name = "partitions",
.dflt_enabled = FALSE,
.idinfos = idinfos,
.nidinfos = ARRAY_SIZE(idinfos),
.has_fltr = TRUE,
.probe = partitions_probe,
.safeprobe = partitions_probe,
.free_data = partitions_free_data
};
/*
* For compatibility with the rest of libblkid API (with the old high-level
* API) we use completely opaque typedefs for all structs. Don't forget that
* the final blkid_* types are pointers! See blkid.h.
*
* [Just for the record, I hate typedef for pointers --kzak]
*/
/* exported as opaque type "blkid_parttable" */
struct blkid_struct_parttable {
const char *type; /* partition table type */
blkid_loff_t offset; /* begin of the partition table */
int nparts; /* number of partitions */
blkid_partition parent; /* parent of nested partition table */
struct list_head t_tabs; /* all tables */
};
/* exported as opaque type "blkid_partition" */
struct blkid_struct_partition {
blkid_loff_t start; /* begin of the partition */
blkid_loff_t size; /* size of the partitions */
int type; /* partition type */
char typestr[37]; /* partition type string (GPT and Mac) */
unsigned long long flags; /* partition flags / attributes */
int partno; /* partition number */
char uuid[37]; /* UUID (when supported by PT), e.g GPT */
unsigned char name[128]; /* Partition in UTF8 name (when supporte by PT), e.g. Mac */
blkid_parttable tab; /* partition table */
};
/* exported as opaque type "blkid_partlist" */
struct blkid_struct_partlist {
int next_partno; /* next partition number */
blkid_partition next_parent; /* next parent if parsing nested PT */
int nparts; /* number of partitions */
int nparts_max; /* max.number of partitions */
blkid_partition parts; /* array of partitions */
struct list_head l_tabs; /* list of partition tables */
};
static int blkid_partitions_probe_partition(blkid_probe pr);
/**
* blkid_probe_enable_partitions:
* @pr: probe
* @enable: TRUE/FALSE
*
* Enables/disables the partitions probing for non-binary interface.
*
* Returns: 0 on success, or -1 in case of error.
*/
int blkid_probe_enable_partitions(blkid_probe pr, int enable)
{
if (!pr)
return -1;
pr->chains[BLKID_CHAIN_PARTS].enabled = enable;
return 0;
}
/**
* blkid_probe_set_partitions_flags:
* @pr: prober
* @flags: BLKID_PARTS_* flags
*
* Sets probing flags to the partitions prober. This function is optional.
*
* Returns: 0 on success, or -1 in case of error.
*/
int blkid_probe_set_partitions_flags(blkid_probe pr, int flags)
{
if (!pr)
return -1;
pr->chains[BLKID_CHAIN_PARTS].flags = flags;
return 0;
}
/**
* blkid_probe_reset_partitions_filter:
* @pr: prober
*
* Resets partitions probing filter
*
* Returns: 0 on success, or -1 in case of error.
*/
int blkid_probe_reset_partitions_filter(blkid_probe pr)
{
return __blkid_probe_reset_filter(pr, BLKID_CHAIN_PARTS);
}
/**
* blkid_probe_invert_partitions_filter:
* @pr: prober
*
* Inverts partitions probing filter
*
* Returns: 0 on success, or -1 in case of error.
*/
int blkid_probe_invert_partitions_filter(blkid_probe pr)
{
return __blkid_probe_invert_filter(pr, BLKID_CHAIN_PARTS);
}
/**
* blkid_probe_filter_partitions_type:
* @pr: prober
* @flag: filter BLKID_FLTR_{NOTIN,ONLYIN} flag
* @names: NULL terminated array of probing function names (e.g. "vfat").
*
* %BLKID_FLTR_NOTIN - probe for all items which are NOT IN @names
*
* %BLKID_FLTR_ONLYIN - probe for items which are IN @names
*
* Returns: 0 on success, or -1 in case of error.
*/
int blkid_probe_filter_partitions_type(blkid_probe pr, int flag, char *names[])
{
return __blkid_probe_filter_types(pr, BLKID_CHAIN_PARTS, flag, names);
}
/**
* blkid_probe_get_partitions:
* @pr: probe
*
* This is a binary interface for partitions. See also blkid_partlist_*
* functions.
*
* This function is independent on blkid_do_[safe,full]probe() and
* blkid_probe_enable_partitions() calls.
*
* WARNING: the returned object will be overwritten by the next
* blkid_probe_get_partitions() call for the same @pr. If you want to
* use more blkid_partlist objects in the same time you have to create
* more blkid_probe handlers (see blkid_new_probe()).
*
* Returns: list of partitions, or NULL in case of error.
*/
blkid_partlist blkid_probe_get_partitions(blkid_probe pr)
{
return (blkid_partlist) blkid_probe_get_binary_data(pr,
&pr->chains[BLKID_CHAIN_PARTS]);
}
/* for internal usage only */
blkid_partlist blkid_probe_get_partlist(blkid_probe pr)
{
return (blkid_partlist) pr->chains[BLKID_CHAIN_PARTS].data;
}
static void blkid_probe_set_partlist(blkid_probe pr, blkid_partlist ls)
{
pr->chains[BLKID_CHAIN_PARTS].data = ls;
}
static void ref_parttable(blkid_parttable tab)
{
tab->nparts++;
}
static void unref_parttable(blkid_parttable tab)
{
tab->nparts--;
if (tab->nparts <= 0) {
list_del(&tab->t_tabs);
free(tab);
}
}
/* free all allocated parttables */
static void free_parttables(blkid_partlist ls)
{
if (!ls || !ls->l_tabs.next)
return;
/* remove unassigned partition tables */
while (!list_empty(&ls->l_tabs)) {
blkid_parttable tab = list_entry(ls->l_tabs.next,
struct blkid_struct_parttable, t_tabs);
unref_parttable(tab);
}
}
static void reset_partlist(blkid_partlist ls)
{
if (!ls)
return;
free_parttables(ls);
if (ls->next_partno) {
/* already initialized - reset */
int tmp_nparts = ls->nparts_max;
blkid_partition tmp_parts = ls->parts;
memset(ls, 0, sizeof(struct blkid_struct_partlist));
ls->nparts_max = tmp_nparts;
ls->parts = tmp_parts;
}
ls->nparts = 0;
ls->next_partno = 1;
INIT_LIST_HEAD(&ls->l_tabs);
DBG(DEBUG_LOWPROBE, printf("partlist reset\n"));
}
static blkid_partlist partitions_init_data(struct blkid_chain *chn)
{
blkid_partlist ls;
if (chn->data)
ls = (blkid_partlist) chn->data;
else {
/* allocate the new list of partitions */
ls = calloc(1, sizeof(struct blkid_struct_partlist));
if (!ls)
return NULL;
chn->data = (void *) ls;
}
reset_partlist(ls);
DBG(DEBUG_LOWPROBE,
printf("parts: initialized partitions list (%p, size=%d)\n",
ls, ls->nparts_max));
return ls;
}
static void partitions_free_data(blkid_probe pr __attribute__((__unused__)),
void *data)
{
blkid_partlist ls = (blkid_partlist) data;
if (!ls)
return;
free_parttables(ls);
/* deallocate partitions and partlist */
free(ls->parts);
free(ls);
}
blkid_parttable blkid_partlist_new_parttable(blkid_partlist ls,
const char *type, blkid_loff_t offset)
{
blkid_parttable tab;
tab = calloc(1, sizeof(struct blkid_struct_parttable));
if (!tab)
return NULL;
tab->type = type;
tab->offset = offset;
tab->parent = ls->next_parent;
INIT_LIST_HEAD(&tab->t_tabs);
list_add_tail(&tab->t_tabs, &ls->l_tabs);
DBG(DEBUG_LOWPROBE,
printf("parts: create a new partition table "
"(%p, type=%s, offset=%"PRId64")\n", tab, type, offset));
return tab;
}
static blkid_partition new_partition(blkid_partlist ls, blkid_parttable tab)
{
blkid_partition par;
if (ls->nparts + 1 > ls->nparts_max) {
/* Linux kernel has DISK_MAX_PARTS=256, but it's too much for
* generic Linux machine -- let start with 32 partititions.
*/
ls->parts = realloc(ls->parts, (ls->nparts_max + 32) *
sizeof(struct blkid_struct_partition));
if (!ls->parts)
return NULL;
ls->nparts_max += 32;
}
par = &ls->parts[ls->nparts++];
memset(par, 0, sizeof(struct blkid_struct_partition));
ref_parttable(tab);
par->tab = tab;
par->partno = blkid_partlist_increment_partno(ls);
return par;
}
blkid_partition blkid_partlist_add_partition(blkid_partlist ls,
blkid_parttable tab,
blkid_loff_t start, blkid_loff_t size)
{
blkid_partition par = new_partition(ls, tab);
if (!par)
return NULL;
par->start = start;
par->size = size;
DBG(DEBUG_LOWPROBE,
printf("parts: add partition (%p start=%"
PRId64 ", size=%" PRId64 ", table=%p)\n",
par, par->start, par->size, tab));
return par;
}
/* allows to modify used partitions numbers (for example for logical partitions) */
int blkid_partlist_set_partno(blkid_partlist ls, int partno)
{
if (!ls)
return -1;
ls->next_partno = partno;
return 0;
}
int blkid_partlist_increment_partno(blkid_partlist ls)
{
return ls ? ls->next_partno++ : -1;
}
/* allows to set "parent" for the next nested partition */
int blkid_partlist_set_parent(blkid_partlist ls, blkid_partition par)
{
if (!ls)
return -1;
ls->next_parent = par;
return 0;
}
blkid_partition blkid_partlist_get_parent(blkid_partlist ls)
{
if (!ls)
return NULL;
return ls->next_parent;
}
int blkid_partitions_need_typeonly(blkid_probe pr)
{
struct blkid_chain *chn = blkid_probe_get_chain(pr);
return chn && chn->data && chn->binary ? FALSE : TRUE;
}
/* get private chain flags */
int blkid_partitions_get_flags(blkid_probe pr)
{
struct blkid_chain *chn = blkid_probe_get_chain(pr);
return chn ? chn->flags : 0;
}
/* check if @start and @size are within @par partition */
int blkid_is_nested_dimension(blkid_partition par,
blkid_loff_t start, blkid_loff_t size)
{
blkid_loff_t pstart;
blkid_loff_t psize;
if (!par)
return 0;
pstart = blkid_partition_get_start(par);
psize = blkid_partition_get_size(par);
if (start < pstart || start + size > pstart + psize)
return 0;
return 1;
}
static int idinfo_probe(blkid_probe pr, const struct blkid_idinfo *id,
struct blkid_chain *chn)
{
const struct blkid_idmag *mag = NULL;
blkid_loff_t off;
int rc = 1; /* = nothing detected */
if (pr->size <= 0 || (id->minsz && id->minsz > pr->size))
goto nothing; /* the device is too small */
if (blkid_probe_get_idmag(pr, id, &off, &mag))
goto nothing;
/* final check by probing function */
if (id->probefunc) {
DBG(DEBUG_LOWPROBE, printf(
"%s: ---> call probefunc()\n", id->name));
rc = id->probefunc(pr, mag);
if (rc == -1) {
/* reset after error */
reset_partlist(blkid_probe_get_partlist(pr));
if (chn && !chn->binary)
blkid_probe_chain_reset_vals(pr, chn);
DBG(DEBUG_LOWPROBE, printf(
"%s probefunc failed\n", id->name));
}
if (rc == 0 && mag && chn && !chn->binary)
rc = blkid_probe_set_magic(pr, off, mag->len,
(unsigned char *) mag->magic);
DBG(DEBUG_LOWPROBE, printf(
"%s: <--- (rc = %d)\n", id->name, rc));
}
nothing:
return rc;
}
/*
* The blkid_do_probe() backend.
*/
static int partitions_probe(blkid_probe pr, struct blkid_chain *chn)
{
int rc = 1;
size_t i;
if (!pr || chn->idx < -1)
return -1;
blkid_probe_chain_reset_vals(pr, chn);
if (chn->binary)
partitions_init_data(chn);
if (!pr->wipe_size && (pr->prob_flags & BLKID_PROBE_FL_IGNORE_PT))
goto details_only;
DBG(DEBUG_LOWPROBE,
printf("--> starting probing loop [PARTS idx=%d]\n",
chn->idx));
i = chn->idx < 0 ? 0 : chn->idx + 1U;
for ( ; i < ARRAY_SIZE(idinfos); i++) {
const char *name;
chn->idx = i;
/* apply filter */
if (chn->fltr && blkid_bmp_get_item(chn->fltr, i))
continue;
/* apply checks from idinfo */
if (idinfo_probe(pr, idinfos[i], chn) != 0)
continue;
name = idinfos[i]->name;
/* all checks passed */
if (!chn->binary)
blkid_probe_set_value(pr, "PTTYPE",
(unsigned char *) name,
strlen(name) + 1);
DBG(DEBUG_LOWPROBE,
printf("<-- leaving probing loop (type=%s) [PARTS idx=%d]\n",
name, chn->idx));
rc = 0;
break;
}
if (rc == 1) {
DBG(DEBUG_LOWPROBE,
printf("<-- leaving probing loop (failed) [PARTS idx=%d]\n",
chn->idx));
}
details_only:
/*
* Gather PART_ENTRY_* values if the current device is a partition.
*/
if (!chn->binary &&
(blkid_partitions_get_flags(pr) & BLKID_PARTS_ENTRY_DETAILS)) {
if (!blkid_partitions_probe_partition(pr))
rc = 0;
}
return rc;
}
/* Probe for nested partition table within the parental partition */
int blkid_partitions_do_subprobe(blkid_probe pr, blkid_partition parent,
const struct blkid_idinfo *id)
{
blkid_probe prc;
int rc = 1;
blkid_partlist ls;
blkid_loff_t sz, off;
DBG(DEBUG_LOWPROBE, printf(
"parts: ----> %s subprobe requested (parent=%p)\n",
id->name, parent));
if (!pr || !parent || !parent->size)
return -1;
/* range defined by parent */
sz = ((blkid_loff_t) parent->size) << 9;
off = ((blkid_loff_t) parent->start) << 9;
if (off < pr->off || pr->off + pr->size < off + sz) {
DBG(DEBUG_LOWPROBE, printf(
"ERROR: parts: <---- '%s' subprobe: overflow detected.\n",
id->name));
return -1;
}
/* create private prober */
prc = blkid_clone_probe(pr);
if (!prc)
return -1;
blkid_probe_set_dimension(prc, off, sz);
/* clone is always with reset chain, fix it */
prc->cur_chain = blkid_probe_get_chain(pr);
/*
* Set 'parent' to the current list of the partitions and use the list
* in cloned prober (so the cloned prober will extend the current list
* of partitions rather than create a new).
*/
ls = blkid_probe_get_partlist(pr);
blkid_partlist_set_parent(ls, parent);
blkid_probe_set_partlist(prc, ls);
rc = idinfo_probe(prc, id, blkid_probe_get_chain(pr));
blkid_probe_set_partlist(prc, NULL);
blkid_partlist_set_parent(ls, NULL);
blkid_free_probe(prc); /* free cloned prober */
DBG(DEBUG_LOWPROBE, printf(
"parts: <---- %s subprobe done (parent=%p, rc=%d)\n",
id->name, parent, rc));
return rc;
}
static int blkid_partitions_probe_partition(blkid_probe pr)
{
int rc = 1;
blkid_probe disk_pr = NULL;
blkid_partlist ls;
blkid_partition par;
dev_t devno;
devno = blkid_probe_get_devno(pr);
if (!devno)
goto nothing;
disk_pr = blkid_probe_get_wholedisk_probe(pr);
if (!disk_pr)
goto nothing;
/* parse PT */
ls = blkid_probe_get_partitions(disk_pr);
if (!ls)
goto nothing;
par = blkid_partlist_devno_to_partition(ls, devno);
if (par) {
const char *v;
blkid_parttable tab = blkid_partition_get_table(par);
dev_t disk = blkid_probe_get_devno(disk_pr);
if (tab) {
v = blkid_parttable_get_type(tab);
if (v)
blkid_probe_set_value(pr, "PART_ENTRY_SCHEME",
(unsigned char *) v, strlen(v) + 1);
}
v = blkid_partition_get_name(par);
if (v)
blkid_probe_set_value(pr, "PART_ENTRY_NAME",
(unsigned char *) v, strlen(v) + 1);
v = blkid_partition_get_uuid(par);
if (v)
blkid_probe_set_value(pr, "PART_ENTRY_UUID",
(unsigned char *) v, strlen(v) + 1);
/* type */
v = blkid_partition_get_type_string(par);
if (v)
blkid_probe_set_value(pr, "PART_ENTRY_TYPE",
(unsigned char *) v, strlen(v) + 1);
else
blkid_probe_sprintf_value(pr, "PART_ENTRY_TYPE",
"0x%x", blkid_partition_get_type(par));
if (blkid_partition_get_flags(par))
blkid_probe_sprintf_value(pr, "PART_ENTRY_FLAGS",
"0x%llx", blkid_partition_get_flags(par));
blkid_probe_sprintf_value(pr, "PART_ENTRY_NUMBER",
"%d", blkid_partition_get_partno(par));
blkid_probe_sprintf_value(pr, "PART_ENTRY_OFFSET", "%jd",
blkid_partition_get_start(par));
blkid_probe_sprintf_value(pr, "PART_ENTRY_SIZE", "%jd",
blkid_partition_get_size(par));
blkid_probe_sprintf_value(pr, "PART_ENTRY_DISK", "%u:%u",
major(disk), minor(disk));
}
rc = 0;
nothing:
return rc;
}
/*
* Returns 1 if the device is whole-disk and the area specified by @offset and
* @size is covered by any partition.
*/
int blkid_probe_is_covered_by_pt(blkid_probe pr,
blkid_loff_t offset, blkid_loff_t size)
{
blkid_probe prc;
blkid_partlist ls = NULL;
blkid_loff_t start, end;
int nparts, i, rc = 0;
DBG(DEBUG_LOWPROBE, printf(
"=> checking if off=%jd size=%jd covered by PT\n",
offset, size));
prc = blkid_clone_probe(pr);
if (!prc)
goto done;
ls = blkid_probe_get_partitions(prc);
if (!ls)
goto done;
nparts = blkid_partlist_numof_partitions(ls);
if (!nparts)
goto done;
end = (offset + size) >> 9;
start = offset >> 9;
/* check if the partition table fits into the device */
for (i = 0; i < nparts; i++) {
blkid_partition par = &ls->parts[i];
if (par->start + par->size > (pr->size >> 9)) {
DBG(DEBUG_LOWPROBE, printf("partition #%d overflows "
"device (off=%" PRId64 " size=%" PRId64 ")\n",
par->partno, par->start, par->size));
goto done;
}
}
/* check if the requested area is covered by PT */
for (i = 0; i < nparts; i++) {
blkid_partition par = &ls->parts[i];
if (start >= par->start && end <= par->start + par->size) {
rc = 1;
break;
}
}
done:
blkid_free_probe(prc);
DBG(DEBUG_LOWPROBE, printf("<= %s covered by PT\n", rc ? "IS" : "NOT"));
return rc;
}
/**
* blkid_known_pttype:
* @pttype: partiton name
*
* Returns: 1 for known or 0 for unknown partition type.
*/
int blkid_known_pttype(const char *pttype)
{
size_t i;
if (!pttype)
return 0;
for (i = 0; i < ARRAY_SIZE(idinfos); i++) {
const struct blkid_idinfo *id = idinfos[i];
if (strcmp(id->name, pttype) == 0)
return 1;
}
return 0;
}
/**
* blkid_partlist_numof_partitions:
* @ls: partitions list
*
* Returns: number of partitions in the list or -1 in case of error.
*/
int blkid_partlist_numof_partitions(blkid_partlist ls)
{
return ls ? ls->nparts : -1;
}
/**
* blkid_partlist_get_table:
* @ls: partitions list
*
* Returns: top-level partition table or NULL of there is not a partition table
* on the device.
*/
blkid_parttable blkid_partlist_get_table(blkid_partlist ls)
{
if (!ls || list_empty(&ls->l_tabs))
return NULL;
return list_entry(ls->l_tabs.next,
struct blkid_struct_parttable, t_tabs);
}
/**
* blkid_partlist_get_partition:
* @ls: partitions list
* @n: partition number in range 0..N, where 'N' is blkid_partlist_numof_partitions().
*
* It's possible that the list of partitions is *empty*, but there is a valid
* partition table on the disk. This happen when on-disk details about
* partitions are unknown or the partition table is empty.
*
* See also blkid_partlist_get_table().
*
* Returns: partition object or NULL in case or error.
*/
blkid_partition blkid_partlist_get_partition(blkid_partlist ls, int n)
{
if (!ls || n < 0 || n >= ls->nparts)
return NULL;
return &ls->parts[n];
}
/**
* blkid_partlist_devno_to_partition:
* @ls: partitions list
* @devno: requested partition
*
* This function tries to get start and size for @devno from sysfs and
* returns a partition from @ls which matches with the values from sysfs.
*
* This function is necessary when you want to make a relation between an entry
* in the partition table (@ls) and block devices in your system.
*
* Returns: partition object or NULL in case or error.
*/
blkid_partition blkid_partlist_devno_to_partition(blkid_partlist ls, dev_t devno)
{
struct sysfs_cxt sysfs;
uint64_t start, size;
int i, rc, partno = 0;
DBG(DEBUG_LOWPROBE,
printf("triyng to convert devno 0x%llx to partition\n",
(long long) devno));
if (sysfs_init(&sysfs, devno, NULL)) {
DBG(DEBUG_LOWPROBE, printf("failed t init sysfs context\n"));
return NULL;
}
rc = sysfs_read_u64(&sysfs, "size", &size);
if (!rc) {
rc = sysfs_read_u64(&sysfs, "start", &start);
if (rc) {
/* try to get partition number from DM uuid.
*/
char *uuid = sysfs_strdup(&sysfs, "dm/uuid");
char *tmp = uuid;
char *prefix = uuid ? strsep(&tmp, "-") : NULL;
if (prefix && strncasecmp(prefix, "part", 4) == 0) {
char *end = NULL;
partno = strtol(prefix + 4, &end, 10);
if (prefix == end || (end && *end))
partno = 0;
else
rc = 0; /* success */
}
free(uuid);
}
}
sysfs_deinit(&sysfs);
if (rc)
return NULL;
if (partno) {
DBG(DEBUG_LOWPROBE, printf("mapped by DM, using partno %d\n", partno));
/*
* Partition mapped by kpartx does not provide "start" offset
* in /sys, but if we know partno and size of the partition
* that we can probably make the releation bettween the device
* and an entry in partition table.
*/
for (i = 0; i < ls->nparts; i++) {
blkid_partition par = &ls->parts[i];
if (partno != blkid_partition_get_partno(par))
continue;
if ((blkid_loff_t) size == blkid_partition_get_size(par) ||
(blkid_partition_is_extended(par) && size <= 1024))
return par;
}
return NULL;
}
DBG(DEBUG_LOWPROBE, printf("searching by offset/size\n"));
for (i = 0; i < ls->nparts; i++) {
blkid_partition par = &ls->parts[i];
if (blkid_partition_get_start(par) == (blkid_loff_t) start &&
blkid_partition_get_size(par) == (blkid_loff_t) size)
return par;
/* exception for extended dos partitions */
if (blkid_partition_get_start(par) == (blkid_loff_t) start &&
blkid_partition_is_extended(par) && size <= 1024)
return par;
}
DBG(DEBUG_LOWPROBE, printf("not found partition for device\n"));
return NULL;
}
int blkid_partition_set_type(blkid_partition par, int type)
{
if (!par)
return -1;
par->type = type;
return 0;
}
/**
* blkid_parttable_get_type:
* @tab: partition table
*
* Returns: partition table type (type name, e.g. "dos", "gpt", ...)
*/
const char *blkid_parttable_get_type(blkid_parttable tab)
{
return tab ? tab->type : NULL;
}
/**
* blkid_parttable_get_parent:
* @tab: partition table
*
* Returns: parent for nexted partitition tables or NULL.
*/
blkid_partition blkid_parttable_get_parent(blkid_parttable tab)
{
return tab ? tab->parent : NULL;
}
/**
* blkid_parttable_get_offset:
* @tab: partition table
*
* Note the position is relative to begin of the device as defined by
* blkid_probe_set_device() for primary partition table, and relative
* to parental partition for nested patition tables.
*
* <informalexample>
* <programlisting>
* off_t offset;
* blkid_partition parent = blkid_parttable_get_parent(tab);
*
* offset = blkid_parttable_get_offset(tab);
*
* if (parent)
* / * 'tab' is nested partition table * /
* offset += blkid_partition_get_start(parent);
* </programlisting>
* </informalexample>
* Returns: position (in bytes) of the partition table or -1 in case of error.
*
*/
blkid_loff_t blkid_parttable_get_offset(blkid_parttable tab)
{
return tab ? tab->offset : -1;
}
/**
* blkid_partition_get_table:
* @par: partition
*
* The "parttable" describes partition table. The table is usually the same for
* all partitions -- except nested partition tables.
*
* For example bsd, solaris, etc. use a nested partition table within
* standard primary dos partition:
*
* <informalexample>
* <programlisting>
*
* -- dos partition table
* 0: sda1 dos primary partition
* 1: sda2 dos primary partition
* -- bsd partition table (with in sda2)
* 2: sda5 bds partition
* 3: sda6 bds partition
*
* </programlisting>
* </informalexample>
*
* The library does not to use a separate partition table object for dos logical
* partitions (partitions within extended partition). It's possible to
* differentiate between logical, extended and primary partitions by
*
* blkid_partition_is_{extended,primary,logical}().
*
* Returns: partition table object or NULL in case of error.
*/
blkid_parttable blkid_partition_get_table(blkid_partition par)
{
return par ? par->tab : NULL;
}
static int partition_get_logical_type(blkid_partition par)
{
blkid_parttable tab;
if (!par)
return -1;
tab = blkid_partition_get_table(par);
if (!tab || !tab->type)
return -1;
if (tab->parent)
return 'L'; /* report nested partitions as logical */
if (!strcmp(tab->type, "dos")) {
if (par->partno > 4)
return 'L'; /* logical */
if(par->type == BLKID_DOS_EXTENDED_PARTITION ||
par->type == BLKID_W95_EXTENDED_PARTITION ||
par->type == BLKID_LINUX_EXTENDED_PARTITION)
return 'E';
}
return 'P';
}
/**
* blkid_partition_is_primary:
* @par: partition
*
* Note, this function returns FALSE for DOS extended partitions and
* all partitions in nested partition tables.
*
* Returns: 1 if the partitions is primary partition or 0 if not.
*/
int blkid_partition_is_primary(blkid_partition par)
{
return partition_get_logical_type(par) == 'P' ? TRUE : FALSE;
}
/**
* blkid_partition_is_extended:
* @par: partition
*
* Returns: 1 if the partitions is extended (dos, windows or linux)
* partition or 0 if not.
*/
int blkid_partition_is_extended(blkid_partition par)
{
return partition_get_logical_type(par) == 'E' ? TRUE : FALSE;
}
/**
* blkid_partition_is_logical:
* @par: partition
*
* Note that this function returns TRUE for all partitions in all
* nested partition tables (e.g. BSD labels).
*
* Returns: 1 if the partitions is logical partition or 0 if not.
*/
int blkid_partition_is_logical(blkid_partition par)
{
return partition_get_logical_type(par) == 'L' ? TRUE : FALSE;
}
static void set_string(unsigned char *item, size_t max,
const unsigned char *data, size_t len)
{
if (len >= max)
len = max - 1;
memcpy(item, data, len);
item[len] = '\0';
blkid_rtrim_whitespace(item);
}
int blkid_partition_set_name(blkid_partition par,
const unsigned char *name, size_t len)
{
if (!par)
return -1;
set_string(par->name, sizeof(par->name), name, len);
return 0;
}
int blkid_partition_set_utf8name(blkid_partition par, const unsigned char *name,
size_t len, int enc)
{
if (!par)
return -1;
blkid_encode_to_utf8(enc, par->name, sizeof(par->name), name, len);
blkid_rtrim_whitespace(par->name);
return 0;
}
int blkid_partition_set_uuid(blkid_partition par, const unsigned char *uuid)
{
if (!par)
return -1;
blkid_unparse_uuid(uuid, par->uuid, sizeof(par->uuid));
return 0;
}
/**
* blkid_partition_get_name:
* @par: partition
*
* Returns: partition name string if supported by PT (e.g. Mac) or NULL.
*/
const char *blkid_partition_get_name(blkid_partition par)
{
return par && *par->name ? (char *) par->name : NULL;
}
/**
* blkid_partition_get_uuid:
* @par: partition
*
* Returns: partition UUID string if supported by PT (e.g. GPT) or NULL.
*/
const char *blkid_partition_get_uuid(blkid_partition par)
{
return par && *par->uuid ? par->uuid : NULL;
}
/**
* blkid_partition_get_partno:
* @par: partition
*
* Returns: proposed partitin number (e.g. 'N' from sda'N') or -1 in case of
* error. Note that the number is generate by library independenly on your OS.
*/
int blkid_partition_get_partno(blkid_partition par)
{
return par ? par->partno : -1;
}
/**
* blkid_partition_get_start:
* @par: partition
*
* Be careful if you _not_ probe whole disk:
*
* 1) the offset is usully relative to begin of the disk -- but if you probe a
* fragment of the disk only -- then the offset could be still relative to
* the begin of the disk rather that relative to the fragment.
*
* 2) the offset for nested partitions could be releative to parent (e.g. Solaris)
* _or_ relative to the begin of the whole disk (e.g. bsd).
*
* You don't have to care about such details if you proble whole disk. In such
* a case libblkid always returns the offset relative to the begin of the disk.
*
* Returns: start of the partition (in 512-sectors).
*/
blkid_loff_t blkid_partition_get_start(blkid_partition par)
{
return par ? par->start : -1;
}
/**
* blkid_partition_get_size:
* @par: partition
*
* WARNING: be very careful when you work with MS-DOS extended partitions. The
* library always returns full size of the partition. If you want add
* the partition to the Linux system (BLKPG_ADD_PARTITION ioctl) you
* need to reduce the size of the partition to 1 or 2 blocks. The
* rest of the partition has to be unaccessible for mkfs or mkswap
* programs, we need a small space for boot loaders only.
*
* For some unknown reason this (safe) practice is not to used for
* nested BSD, Solaris, ..., partition tables in Linux kernel.
*
* Returns: size of the partition (in 512-sectors).
*/
blkid_loff_t blkid_partition_get_size(blkid_partition par)
{
return par ? par->size : -1;
}
/**
* blkid_partition_get_type:
* @par: partition
*
* Returns: partition type.
*/
int blkid_partition_get_type(blkid_partition par)
{
return par ? par->type : 0;
}
/* Sets partition 'type' for PT where the type is defined by string rather
* than by number
*/
int blkid_partition_set_type_string(blkid_partition par,
const unsigned char *type, size_t len)
{
if (!par)
return -1;
set_string((unsigned char *) par->typestr,
sizeof(par->typestr), type, len);
return 0;
}
/* Sets partition 'type' for PT where the type is defined by UUIDrather
* than by number
*/
int blkid_partition_set_type_uuid(blkid_partition par, const unsigned char *uuid)
{
if (!par)
return -1;
blkid_unparse_uuid(uuid, par->typestr, sizeof(par->typestr));
return 0;
}
/**
* blkid_partition_get_type_string:
* @par: partition
*
* The type string is supported by a small subset of partition tables (e.g Mac
* and EFI GPT). Note that GPT uses type UUID and this function returns this
* UUID as string.
*
* Returns: partition type string or NULL.
*/
const char *blkid_partition_get_type_string(blkid_partition par)
{
return par && *par->typestr ? par->typestr : NULL;
}
int blkid_partition_set_flags(blkid_partition par, unsigned long long flags)
{
if (!par)
return -1;
par->flags = flags;
return 0;
}
/**
* blkid_partition_get_flags
* @par: partition
*
* Returns: partition flags (or attributes for gpt).
*/
unsigned long long blkid_partition_get_flags(blkid_partition par)
{
return par ? par->flags : 0;
}