Improve wlr_drm_format documentation

A wlroots user can easily get confused and think that `cap` refers to
wlroots buffer capabilities, not array capacity.
This commit is contained in:
Demi Marie Obenour 2021-11-15 09:44:12 -05:00 committed by Simon Zeni
parent a04cfca4da
commit b5d4bc3c62
2 changed files with 36 additions and 17 deletions

View File

@ -5,19 +5,38 @@
#include <stddef.h> #include <stddef.h>
#include <stdint.h> #include <stdint.h>
/** A single DRM format */
struct wlr_drm_format { struct wlr_drm_format {
// The actual DRM format, from `drm_fourcc.h`
uint32_t format; uint32_t format;
size_t len, cap; // The number of modifiers
size_t len;
// The capacity of the array; do not use.
size_t capacity;
// The actual modifiers
uint64_t modifiers[]; uint64_t modifiers[];
}; };
/** A set of DRM formats */
struct wlr_drm_format_set { struct wlr_drm_format_set {
size_t len, cap; // The number of formats
size_t len;
// The capacity of the array; private to wlroots
size_t capacity;
// A pointer to an array of `struct wlr_drm_format *` of length `len`.
struct wlr_drm_format **formats; struct wlr_drm_format **formats;
}; };
/**
* Free all of the DRM formats in the set, making the set empty. Does not
* free the set itself.
*/
void wlr_drm_format_set_finish(struct wlr_drm_format_set *set); void wlr_drm_format_set_finish(struct wlr_drm_format_set *set);
/**
* Return a pointer to a member of this `wlr_drm_format_set` of format
* `format`, or NULL if none exists.
*/
const struct wlr_drm_format *wlr_drm_format_set_get( const struct wlr_drm_format *wlr_drm_format_set_get(
const struct wlr_drm_format_set *set, uint32_t format); const struct wlr_drm_format_set *set, uint32_t format);

View File

@ -15,7 +15,7 @@ void wlr_drm_format_set_finish(struct wlr_drm_format_set *set) {
free(set->formats); free(set->formats);
set->len = 0; set->len = 0;
set->cap = 0; set->capacity = 0;
set->formats = NULL; set->formats = NULL;
} }
@ -74,8 +74,8 @@ bool wlr_drm_format_set_add(struct wlr_drm_format_set *set, uint32_t format,
return false; return false;
} }
if (set->len == set->cap) { if (set->len == set->capacity) {
size_t new = set->cap ? set->cap * 2 : 4; size_t new = set->capacity ? set->capacity * 2 : 4;
struct wlr_drm_format **tmp = realloc(set->formats, struct wlr_drm_format **tmp = realloc(set->formats,
sizeof(*fmt) + sizeof(fmt->modifiers[0]) * new); sizeof(*fmt) + sizeof(fmt->modifiers[0]) * new);
@ -85,7 +85,7 @@ bool wlr_drm_format_set_add(struct wlr_drm_format_set *set, uint32_t format,
return false; return false;
} }
set->cap = new; set->capacity = new;
set->formats = tmp; set->formats = tmp;
} }
@ -94,15 +94,15 @@ bool wlr_drm_format_set_add(struct wlr_drm_format_set *set, uint32_t format,
} }
struct wlr_drm_format *wlr_drm_format_create(uint32_t format) { struct wlr_drm_format *wlr_drm_format_create(uint32_t format) {
size_t cap = 4; size_t capacity = 4;
struct wlr_drm_format *fmt = struct wlr_drm_format *fmt =
calloc(1, sizeof(*fmt) + sizeof(fmt->modifiers[0]) * cap); calloc(1, sizeof(*fmt) + sizeof(fmt->modifiers[0]) * capacity);
if (!fmt) { if (!fmt) {
wlr_log_errno(WLR_ERROR, "Allocation failed"); wlr_log_errno(WLR_ERROR, "Allocation failed");
return NULL; return NULL;
} }
fmt->format = format; fmt->format = format;
fmt->cap = cap; fmt->capacity = capacity;
return fmt; return fmt;
} }
@ -119,16 +119,16 @@ bool wlr_drm_format_add(struct wlr_drm_format **fmt_ptr, uint64_t modifier) {
} }
} }
if (fmt->len == fmt->cap) { if (fmt->len == fmt->capacity) {
size_t cap = fmt->cap ? fmt->cap * 2 : 4; size_t capacity = fmt->capacity ? fmt->capacity * 2 : 4;
fmt = realloc(fmt, sizeof(*fmt) + sizeof(fmt->modifiers[0]) * cap); fmt = realloc(fmt, sizeof(*fmt) + sizeof(fmt->modifiers[0]) * capacity);
if (!fmt) { if (!fmt) {
wlr_log_errno(WLR_ERROR, "Allocation failed"); wlr_log_errno(WLR_ERROR, "Allocation failed");
return false; return false;
} }
fmt->cap = cap; fmt->capacity = capacity;
*fmt_ptr = fmt; *fmt_ptr = fmt;
} }
@ -137,9 +137,9 @@ bool wlr_drm_format_add(struct wlr_drm_format **fmt_ptr, uint64_t modifier) {
} }
struct wlr_drm_format *wlr_drm_format_dup(const struct wlr_drm_format *format) { struct wlr_drm_format *wlr_drm_format_dup(const struct wlr_drm_format *format) {
assert(format->len <= format->cap); assert(format->len <= format->capacity);
size_t format_size = sizeof(struct wlr_drm_format) + size_t format_size = sizeof(struct wlr_drm_format) +
format->cap * sizeof(format->modifiers[0]); format->capacity * sizeof(format->modifiers[0]);
struct wlr_drm_format *duped_format = malloc(format_size); struct wlr_drm_format *duped_format = malloc(format_size);
if (duped_format == NULL) { if (duped_format == NULL) {
return NULL; return NULL;
@ -171,12 +171,12 @@ struct wlr_drm_format *wlr_drm_format_intersect(
return NULL; return NULL;
} }
format->format = a->format; format->format = a->format;
format->cap = format_cap; format->capacity = format_cap;
for (size_t i = 0; i < a->len; i++) { for (size_t i = 0; i < a->len; i++) {
for (size_t j = 0; j < b->len; j++) { for (size_t j = 0; j < b->len; j++) {
if (a->modifiers[i] == b->modifiers[j]) { if (a->modifiers[i] == b->modifiers[j]) {
assert(format->len < format->cap); assert(format->len < format->capacity);
format->modifiers[format->len] = a->modifiers[i]; format->modifiers[format->len] = a->modifiers[i];
format->len++; format->len++;
break; break;