mirrors
/
qoi
mirror of https://github.com/phoboslab/qoi.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Fix #22: avoid UB when reading ints from the stream;

This commit is contained in:
Dominic Szablewski 2021-11-26 13:22:00 +01:00
parent 30f8a39ec8
commit dd0b04b319
1 changed files with 31 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

45
qoi.h
View File

@ -241,16 +241,33 @@ void *qoi_decode(const void *data, int size, int *out_w, int *out_h, int channel
#define QOI_HEADER_SIZE 12
#define QOI_PADDING 4
#define QOI_READ_16(B, P) ((B[P++] & 0xff) << 8 | (B[P++] & 0xff))
#define QOI_READ_32(B, P) (QOI_READ_16(B, P) << 16 | QOI_READ_16(B, P))
#define QOI_WRITE_16(B, P, V) (B[P++] = (0xff00 & V) >> 8, B[P++] = (0xff & V))
#define QOI_WRITE_32(B, P, V) (QOI_WRITE_16(B, P, V >> 16), QOI_WRITE_16(B, P, V))
typedef union {
struct { unsigned char r, g, b, a; } rgba;
unsigned int v;
} qoi_rgba_t;
void qoi_write_16(unsigned char *bytes, int *p, unsigned short v) {
bytes[(*p)++] = (0xff00 & v) >> 8;
bytes[(*p)++] = (0xff & v);
}
void qoi_write_32(unsigned char *bytes, int *p, unsigned int v) {
qoi_write_16(bytes, p, (v & 0xffff0000) >> 16);
qoi_write_16(bytes, p, (v & 0xffff));
}
unsigned int qoi_read_16(const unsigned char *bytes, int *p) {
unsigned int a = bytes[(*p)++];
unsigned int b = bytes[(*p)++];
return (a << 8) | b;
}
unsigned int qoi_read_32(const unsigned char *bytes, int *p) {
unsigned int a = qoi_read_16(bytes, p);
unsigned int b = qoi_read_16(bytes, p);
return (a << 16) | b;
}
void *qoi_encode(const void *data, int w, int h, int channels, int *out_len) {
if (
data == NULL || out_len == NULL ||
@ -268,10 +285,10 @@ void *qoi_encode(const void *data, int w, int h, int channels, int *out_len) {
return NULL;
}
QOI_WRITE_32(bytes, p, QOI_MAGIC);
QOI_WRITE_16(bytes, p, w);
QOI_WRITE_16(bytes, p, h);
QOI_WRITE_32(bytes, p, 0); // size, will be set later
qoi_write_32(bytes, &p, QOI_MAGIC);
qoi_write_16(bytes, &p, w);
qoi_write_16(bytes, &p, h);
qoi_write_32(bytes, &p, 0); // size, will be set later
const unsigned char *pixels = (const unsigned char *)data;
@ -367,7 +384,7 @@ void *qoi_encode(const void *data, int w, int h, int channels, int *out_len) {
*out_len = p;
p = 8;
QOI_WRITE_32(bytes, p, data_len);
qoi_write_32(bytes, &p, data_len);
return bytes;
}
@ -379,10 +396,10 @@ void *qoi_decode(const void *data, int size, int *out_w, int *out_h, int channel
const unsigned char *bytes = (const unsigned char *)data;
int p = 0;
int magic = QOI_READ_32(bytes, p);
int w = QOI_READ_16(bytes, p);
int h = QOI_READ_16(bytes, p);
int data_len = QOI_READ_32(bytes, p);
int magic = qoi_read_32(bytes, &p);
int w = qoi_read_16(bytes, &p);
int h = qoi_read_16(bytes, &p);
int data_len = qoi_read_32(bytes, &p);
if (
w == 0 || h == 0 || magic != QOI_MAGIC ||