Skip to content

Commit

Permalink
libfdisk: (gpt) make mode more readable
Browse files Browse the repository at this point in the history 
* use check_ prefix for checking functions
* use plural in function names where we work with more partitions than one
* always use "ents" when when we work with gpt entries array

Signed-off-by: Karel Zak <kzak@redhat.com>
  • Loading branch information
@karelzak
karelzak committed Nov 10, 2014
1 parent a56b70f commit 8ccfcf7
Showing 1 changed file with 43 additions and 39 deletions.
82 changes: 43 additions & 39 deletions libfdisk/src/gpt.c
View file
Expand Up @@ -948,15 +948,16 @@ static int gpt_locate_disklabel(struct fdisk_context *cxt, int n,
/*
* Returns the number of partitions that are in use.
*/
static unsigned partitions_in_use(struct gpt_header *header, struct gpt_entry *e)
static unsigned partitions_in_use(struct gpt_header *header,
struct gpt_entry *ents)
{
uint32_t i, used = 0;

if (!header || ! e)
if (!header || ! ents)
return 0;

for (i = 0; i < le32_to_cpu(header->npartition_entries); i++)
if (!partition_unused(&e[i]))
if (!partition_unused(&ents[i]))
used++;
return used;
}
Expand All @@ -966,15 +967,15 @@ static unsigned partitions_in_use(struct gpt_header *header, struct gpt_entry *e
* Check if a partition is too big for the disk (sectors).
* Returns the faulting partition number, otherwise 0.
*/
static uint32_t partition_check_too_big(struct gpt_header *header,
struct gpt_entry *e, uint64_t sectors)
static uint32_t check_too_big_partitions(struct gpt_header *header,
struct gpt_entry *ents, uint64_t sectors)
{
uint32_t i;

for (i = 0; i < le32_to_cpu(header->npartition_entries); i++) {
if (partition_unused(&e[i]))
if (partition_unused(&ents[i]))
continue;
if (gpt_partition_end(&e[i]) >= sectors)
if (gpt_partition_end(&ents[i]) >= sectors)
return i + 1;
}

Expand All @@ -985,14 +986,15 @@ static uint32_t partition_check_too_big(struct gpt_header *header,
* Check if a partition ends before it begins
* Returns the faulting partition number, otherwise 0.
*/
static uint32_t partition_start_after_end(struct gpt_header *header, struct gpt_entry *e)
static uint32_t check_start_after_end_paritions(struct gpt_header *header,
struct gpt_entry *ents)
{
uint32_t i;

for (i = 0; i < le32_to_cpu(header->npartition_entries); i++) {
if (partition_unused(&e[i]))
if (partition_unused(&ents[i]))
continue;
if (gpt_partition_start(&e[i]) > gpt_partition_end(&e[i]))
if (gpt_partition_start(&ents[i]) > gpt_partition_end(&ents[i]))
return i + 1;
}

Expand All @@ -1015,16 +1017,17 @@ static inline int partition_overlap(struct gpt_entry *e1, struct gpt_entry *e2)
/*
* Find any partitions that overlap.
*/
static uint32_t partition_check_overlaps(struct gpt_header *header, struct gpt_entry *e)
static uint32_t check_overlap_partitions(struct gpt_header *header,
struct gpt_entry *ents)
{
uint32_t i, j;

for (i = 0; i < le32_to_cpu(header->npartition_entries); i++)
for (j = 0; j < i; j++) {
if (partition_unused(&e[i]) ||
partition_unused(&e[j]))
if (partition_unused(&ents[i]) ||
partition_unused(&ents[j]))
continue;
if (partition_overlap(&e[i], &e[j])) {
if (partition_overlap(&ents[i], &ents[j])) {
DBG(LABEL, ul_debug("GPT partitions overlap detected [%u vs. %u]", i, j));
return i + 1;
}
Expand All @@ -1038,14 +1041,14 @@ static uint32_t partition_check_overlaps(struct gpt_header *header, struct gpt_e
* there are no available blocks left, or error. From gdisk.
*/
static uint64_t find_first_available(struct gpt_header *header,
struct gpt_entry *e, uint64_t start)
struct gpt_entry *ents, uint64_t start)
{
uint64_t first;
uint32_t i, first_moved = 0;

uint64_t fu, lu;

if (!header || !e)
if (!header || !ents)
return 0;

fu = le64_to_cpu(header->first_usable_lba);
Expand All @@ -1067,12 +1070,12 @@ static uint64_t find_first_available(struct gpt_header *header,
do {
first_moved = 0;
for (i = 0; i < le32_to_cpu(header->npartition_entries); i++) {
if (partition_unused(&e[i]))
if (partition_unused(&ents[i]))
continue;
if (first < gpt_partition_start(&e[i]))
if (first < gpt_partition_start(&ents[i]))
continue;
if (first <= gpt_partition_end(&e[i])) {
first = gpt_partition_end(&e[i]) + 1;
if (first <= gpt_partition_end(&ents[i])) {
first = gpt_partition_end(&ents[i]) + 1;
first_moved = 1;
}
}
Expand All @@ -1087,18 +1090,18 @@ static uint64_t find_first_available(struct gpt_header *header,

/* Returns last available sector in the free space pointed to by start. From gdisk. */
static uint64_t find_last_free(struct gpt_header *header,
struct gpt_entry *e, uint64_t start)
struct gpt_entry *ents, uint64_t start)
{
uint32_t i;
uint64_t nearest_start;

if (!header || !e)
if (!header || !ents)
return 0;

nearest_start = le64_to_cpu(header->last_usable_lba);

for (i = 0; i < le32_to_cpu(header->npartition_entries); i++) {
uint64_t ps = gpt_partition_start(&e[i]);
uint64_t ps = gpt_partition_start(&ents[i]);

if (nearest_start > ps && ps > start)
nearest_start = ps - 1;
Expand All @@ -1109,22 +1112,22 @@ static uint64_t find_last_free(struct gpt_header *header,

/* Returns the last free sector on the disk. From gdisk. */
static uint64_t find_last_free_sector(struct gpt_header *header,
struct gpt_entry *e)
struct gpt_entry *ents)
{
uint32_t i, last_moved;
uint64_t last = 0;

if (!header || !e)
if (!header || !ents)
goto done;

/* start by assuming the last usable LBA is available */
last = le64_to_cpu(header->last_usable_lba);
do {
last_moved = 0;
for (i = 0; i < le32_to_cpu(header->npartition_entries); i++) {
if ((last >= gpt_partition_start(&e[i])) &&
(last <= gpt_partition_end(&e[i]))) {
last = gpt_partition_start(&e[i]) - 1;
if ((last >= gpt_partition_start(&ents[i])) &&
(last <= gpt_partition_end(&ents[i]))) {
last = gpt_partition_start(&ents[i]) - 1;
last_moved = 1;
}
}
Expand All @@ -1138,18 +1141,19 @@ static uint64_t find_last_free_sector(struct gpt_header *header,
* space on the disk. Returns 0 if there are no available blocks left.
* From gdisk.
*/
static uint64_t find_first_in_largest(struct gpt_header *header, struct gpt_entry *e)
static uint64_t find_first_in_largest(struct gpt_header *header,
struct gpt_entry *ents)
{
uint64_t start = 0, first_sect, last_sect;
uint64_t segment_size, selected_size = 0, selected_segment = 0;

if (!header || !e)
if (!header || !ents)
goto done;

do {
first_sect = find_first_available(header, e, start);
first_sect = find_first_available(header, ents, start);
if (first_sect != 0) {
last_sect = find_last_free(header, e, first_sect);
last_sect = find_last_free(header, ents, first_sect);
segment_size = last_sect - first_sect + 1;

if (segment_size > selected_size) {
Expand All @@ -1169,7 +1173,7 @@ static uint64_t find_first_in_largest(struct gpt_header *header, struct gpt_entr
* they reside, and the size of the largest of those segments. From gdisk.
*/
static uint64_t get_free_sectors(struct fdisk_context *cxt, struct gpt_header *header,
struct gpt_entry *e, uint32_t *nsegments,
struct gpt_entry *ents, uint32_t *nsegments,
uint64_t *largest_segment)
{
uint32_t num = 0;
Expand All @@ -1181,9 +1185,9 @@ static uint64_t get_free_sectors(struct fdisk_context *cxt, struct gpt_header *h
goto done;

do {
first_sect = find_first_available(header, e, start);
first_sect = find_first_available(header, ents, start);
if (first_sect) {
last_sect = find_last_free(header, e, first_sect);
last_sect = find_last_free(header, ents, first_sect);
segment_sz = last_sect - first_sect + 1;

if (segment_sz > largest_seg)
Expand Down Expand Up @@ -1695,7 +1699,7 @@ static int gpt_write_disklabel(struct fdisk_context *cxt)
/* TODO: correct this (with user authorization) and write */
goto err0;

if (partition_check_overlaps(gpt->pheader, gpt->ents))
if (check_overlap_partitions(gpt->pheader, gpt->ents))
goto err0;

/* recompute CRCs for both headers */
Expand Down Expand Up @@ -1808,21 +1812,21 @@ static int gpt_verify_disklabel(struct fdisk_context *cxt)
fdisk_warnx(cxt, _("Primary and backup header mismatch."));
}

ptnum = partition_check_overlaps(gpt->pheader, gpt->ents);
ptnum = check_overlap_partitions(gpt->pheader, gpt->ents);
if (ptnum) {
nerror++;
fdisk_warnx(cxt, _("Partition %u overlaps with partition %u."),
ptnum, ptnum+1);
}

ptnum = partition_check_too_big(gpt->pheader, gpt->ents, cxt->total_sectors);
ptnum = check_too_big_partitions(gpt->pheader, gpt->ents, cxt->total_sectors);
if (ptnum) {
nerror++;
fdisk_warnx(cxt, _("Partition %u is too big for the disk."),
ptnum);
}

ptnum = partition_start_after_end(gpt->pheader, gpt->ents);
ptnum = check_start_after_end_paritions(gpt->pheader, gpt->ents);
if (ptnum) {
nerror++;
fdisk_warnx(cxt, _("Partition %u ends before it starts."),
Expand Down

0 comments on commit 8ccfcf7

Please sign in to comment.