Tidy up opj_ callback functions in fx_codec_jpx_obj.cpp
This is code cleanup rather than bug fixing.
The motivation for this was to fix the casts at line 97 of the original file. These are wrong; you cannot correct via casting a function signature mismatch when passing a function as an argument. In theory, there's no reason to believe that the compiler will pass args in the same manner for a function of type (void*, size_t, void*) as for a function of type (void*, size_t, some_struct*). The cast will suppress the compile error, but you can't be assured the call will work as intended. In practice, it does, since the last architecture where a void* had a different representation than a struct* went extinct in the late 80s.
In the functions themselves, note that we currently bail out if srcData->offset >= srcData->src_size, so the expression
bufferLength = (OPJ_SIZE_T)(srcData->src_size - srcData->offset)
will always be > 0. Hence the check
if(bufferLength <= 0)
is pointless, esp. since bufferLength is a signed type and < 0 makes no sense.
The opj_seek_from_memory() has a bool return value, so returning -1 on error doesn't seem reasonable. Change this to TRUE/FALSE, and return false on seek past end.
If we're truly passing readonly data, then perhaps it makes sense to make the write() function always return -1. I didn't do this.
Lastly, I capitalize "DecodeData" so that it looks like a struct, and change its members to be size_t's to avoid casting back and forth.
R=jun_fang@foxitsoftware.com
Review URL: https://codereview.chromium.org/507273003
diff --git a/core/src/fxcodec/codec/fx_codec_jpx_opj.cpp b/core/src/fxcodec/codec/fx_codec_jpx_opj.cpp
index 5ae7555..595d4df6 100644
--- a/core/src/fxcodec/codec/fx_codec_jpx_opj.cpp
+++ b/core/src/fxcodec/codec/fx_codec_jpx_opj.cpp
@@ -20,69 +20,59 @@
{
(void)client_data;
}
-typedef struct {
- const unsigned char* src_data;
- int src_size;
- int offset;
-} decodeData;
-static OPJ_SIZE_T opj_read_from_memory (void * p_buffer, OPJ_SIZE_T p_nb_bytes, decodeData* srcData)
+struct DecodeData {
+ unsigned char* src_data;
+ OPJ_SIZE_T src_size;
+ OPJ_SIZE_T offset;
+};
+static OPJ_SIZE_T opj_read_from_memory (void * p_buffer, OPJ_SIZE_T p_nb_bytes, void* p_user_data)
{
- if(srcData == NULL || srcData->src_size == 0 || srcData->src_data == NULL || srcData->offset >= srcData->src_size) {
+ DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
+ if (srcData == NULL || srcData->src_size == 0 || srcData->src_data == NULL || srcData->offset >= srcData->src_size) {
return -1;
}
- OPJ_SIZE_T readlength = p_nb_bytes;
- OPJ_SIZE_T bufferLength = (OPJ_SIZE_T)(srcData->src_size - srcData->offset);
- if(bufferLength <= 0) {
- return 0;
- }
- if(bufferLength <= p_nb_bytes) {
- readlength = bufferLength;
- }
- memcpy(p_buffer, &(srcData->src_data[srcData->offset]), readlength);
- srcData->offset += (int)readlength;
+ OPJ_SIZE_T bufferLength = srcData->src_size - srcData->offset;
+ OPJ_SIZE_T readlength = p_nb_bytes < bufferLength ? p_nb_bytes : bufferLength;
+ memcpy(p_buffer, &srcData->src_data[srcData->offset], readlength);
+ srcData->offset += readlength;
return readlength;
}
-static OPJ_SIZE_T opj_write_from_memory (void * p_buffer, OPJ_SIZE_T p_nb_bytes, decodeData* srcData)
+static OPJ_SIZE_T opj_write_from_memory (void * p_buffer, OPJ_SIZE_T p_nb_bytes, void* p_user_data)
{
- if(srcData == NULL || srcData->src_size == 0 || srcData->src_data == NULL || srcData->offset >= srcData->src_size) {
+ DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
+ if (srcData == NULL || srcData->src_size == 0 || srcData->src_data == NULL || srcData->offset >= srcData->src_size) {
return -1;
}
- OPJ_SIZE_T writeLength = p_nb_bytes;
- OPJ_SIZE_T bufferLength = (OPJ_SIZE_T)(srcData->src_size - srcData->offset);
- if(bufferLength <= p_nb_bytes) {
- writeLength = bufferLength;
- }
- memcpy((void*&)(srcData->src_data[srcData->offset]), p_buffer, writeLength);
- srcData->offset += (int)writeLength;
+ OPJ_SIZE_T bufferLength = srcData->src_size - srcData->offset;
+ OPJ_SIZE_T writeLength = p_nb_bytes < bufferLength ? p_nb_bytes : bufferLength;
+ memcpy(&srcData->src_data[srcData->offset], p_buffer, writeLength);
+ srcData->offset += writeLength;
return writeLength;
}
-static OPJ_OFF_T opj_skip_from_memory (OPJ_OFF_T p_nb_bytes, decodeData* srcData)
+static OPJ_OFF_T opj_skip_from_memory (OPJ_OFF_T p_nb_bytes, void* p_user_data)
{
- if(srcData == NULL || srcData->src_size == 0 || srcData->src_data == NULL || srcData->offset >= srcData->src_size) {
+ DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
+ if (srcData == NULL || srcData->src_size == 0 || srcData->src_data == NULL || srcData->offset >= srcData->src_size) {
return -1;
}
- OPJ_OFF_T postion = srcData->offset + p_nb_bytes;
- if(postion < 0 ) {
- postion = 0;
- } else if (postion > srcData->src_size) {
- }
- srcData->offset = (int)postion;
- return p_nb_bytes;
+ OPJ_SIZE_T bufferLength = srcData->src_size - srcData->offset;
+ OPJ_SIZE_T skipLength = p_nb_bytes < bufferLength ? p_nb_bytes : bufferLength;
+ srcData->offset += skipLength;
+ return skipLength;
}
-static OPJ_BOOL opj_seek_from_memory (OPJ_OFF_T p_nb_bytes, decodeData * srcData)
+static OPJ_BOOL opj_seek_from_memory (OPJ_OFF_T p_nb_bytes, void* p_user_data)
{
- if(srcData == NULL || srcData->src_size == 0 || srcData->src_data == NULL || srcData->offset >= srcData->src_size) {
- return -1;
+ DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
+ if (srcData == NULL || srcData->src_size == 0 || srcData->src_data == NULL || srcData->offset >= srcData->src_size) {
+ return OPJ_FALSE;
}
- srcData->offset = (int)p_nb_bytes;
- if(srcData->offset < 0) {
- srcData->offset = 0;
- } else if(srcData->offset > srcData->src_size) {
- srcData->offset = srcData->src_size;
+ if (p_nb_bytes >= srcData->src_size) {
+ return OPJ_FALSE;
}
+ srcData->offset = p_nb_bytes;
return OPJ_TRUE;
}
-opj_stream_t* fx_opj_stream_create_memory_stream (decodeData* data, OPJ_SIZE_T p_size, OPJ_BOOL p_is_read_stream)
+opj_stream_t* fx_opj_stream_create_memory_stream (DecodeData* data, OPJ_SIZE_T p_size, OPJ_BOOL p_is_read_stream)
{
opj_stream_t* l_stream = 00;
if (!data || ! data->src_data || data->src_size <= 0 ) {
@@ -94,10 +84,10 @@
}
opj_stream_set_user_data_v3(l_stream, data, NULL);
opj_stream_set_user_data_length(l_stream, data->src_size);
- opj_stream_set_read_function(l_stream, (opj_stream_read_fn) opj_read_from_memory);
- opj_stream_set_write_function(l_stream, (opj_stream_write_fn) opj_write_from_memory);
- opj_stream_set_skip_function(l_stream, (opj_stream_skip_fn) opj_skip_from_memory);
- opj_stream_set_seek_function(l_stream, (opj_stream_seek_fn) opj_seek_from_memory);
+ opj_stream_set_read_function(l_stream, opj_read_from_memory);
+ opj_stream_set_write_function(l_stream, opj_write_from_memory);
+ opj_stream_set_skip_function(l_stream, opj_skip_from_memory);
+ opj_stream_set_seek_function(l_stream, opj_seek_from_memory);
return l_stream;
}
static void sycc_to_rgb(int offset, int upb, int y, int cb, int cr,
@@ -588,10 +578,10 @@
image = NULL;
m_SrcData = src_data;
m_SrcSize = src_size;
- decodeData srcData;
+ DecodeData srcData;
srcData.offset = 0;
srcData.src_size = src_size;
- srcData.src_data = src_data;
+ srcData.src_data = const_cast<unsigned char*>(src_data);
l_stream = fx_opj_stream_create_memory_stream(&srcData, OPJ_J2K_STREAM_CHUNK_SIZE, 1);
if (l_stream == NULL) {
return FALSE;
