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fix confusion between unsigned <-> U32

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as suggested in #1441.

generally U32 and unsigned are the same thing,
except when they are not ...

case : 32-bit compilation for MIPS (uint32_t == unsigned long)

A vast majority of transformation consists in transforming U32 into unsigned.
In rare cases, it's the other way around (typically for internal code, such as seeds).

Among a few issues this patches solves :
- some parameters were declared with type `unsigned` in *.h,
  but with type `U32` in their implementation *.c .
- some parameters have type unsigned*,
  but the caller user a pointer to U32 instead.

These fixes are useful.

However, the bulk of changes is about %u formating,
which requires unsigned type,
but generally receives U32 values instead,
often just for brevity (U32 is shorter than unsigned).
These changes are generally minor, or even annoying.

As a consequence, the amount of code changed is larger than I would expect for such a patch.

Testing is also a pain :
it requires manually modifying `mem.h`,
in order to lie about `U32`
and force it to be an `unsigned long` typically.
On a 64-bit system, this will break the equivalence unsigned == U32.
Unfortunately, it will also break a few static_assert(), controlling structure sizes.
So it also requires modifying `debug.h` to make `static_assert()` a noop.
And then reverting these changes.

So it's inconvenient, and as a consequence,
this property is currently not checked during CI tests.
Therefore, these problems can emerge again in the future.

I wonder if it is worth ensuring proper distinction of U32 != unsigned in CI tests.
It's another restriction for coding, adding more frustration during merge tests,
since most platforms don't need this distinction (hence contributor will not see it),
and while this can matter in theory, the number of platforms impacted seems minimal.

Thoughts ?
This commit is contained in:
Yann Collet
2018-12-21 16:19:44 -08:00
parent 8f35c7f94c
commit ededcfca57
30 changed files with 401 additions and 388 deletions
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16
contrib/seekable_format/zstdseek_decompress.c
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@ -201,7 +201,7 @@ size_t ZSTD_seekable_free(ZSTD_seekable* zs)
* Performs a binary search to find the last frame with a decompressed offset
* <= pos
* @return : the frame's index */
U32 ZSTD_seekable_offsetToFrameIndex(ZSTD_seekable* const zs, unsigned long long pos)
unsigned ZSTD_seekable_offsetToFrameIndex(ZSTD_seekable* const zs, unsigned long long pos)
{
U32 lo = 0;
U32 hi = (U32)zs->seekTable.tableLen;
@ -222,32 +222,32 @@ U32 ZSTD_seekable_offsetToFrameIndex(ZSTD_seekable* const zs, unsigned long long
return lo;
}
U32 ZSTD_seekable_getNumFrames(ZSTD_seekable* const zs)
unsigned ZSTD_seekable_getNumFrames(ZSTD_seekable* const zs)
{
assert(zs->seekTable.tableLen <= UINT_MAX);
return (U32)zs->seekTable.tableLen;
return (unsigned)zs->seekTable.tableLen;
}
unsigned long long ZSTD_seekable_getFrameCompressedOffset(ZSTD_seekable* const zs, U32 frameIndex)
unsigned long long ZSTD_seekable_getFrameCompressedOffset(ZSTD_seekable* const zs, unsigned frameIndex)
{
if (frameIndex >= zs->seekTable.tableLen) return ZSTD_SEEKABLE_FRAMEINDEX_TOOLARGE;
return zs->seekTable.entries[frameIndex].cOffset;
}
unsigned long long ZSTD_seekable_getFrameDecompressedOffset(ZSTD_seekable* const zs, U32 frameIndex)
unsigned long long ZSTD_seekable_getFrameDecompressedOffset(ZSTD_seekable* const zs, unsigned frameIndex)
{
if (frameIndex >= zs->seekTable.tableLen) return ZSTD_SEEKABLE_FRAMEINDEX_TOOLARGE;
return zs->seekTable.entries[frameIndex].dOffset;
}
size_t ZSTD_seekable_getFrameCompressedSize(ZSTD_seekable* const zs, U32 frameIndex)
size_t ZSTD_seekable_getFrameCompressedSize(ZSTD_seekable* const zs, unsigned frameIndex)
{
if (frameIndex >= zs->seekTable.tableLen) return ERROR(frameIndex_tooLarge);
return zs->seekTable.entries[frameIndex + 1].cOffset -
zs->seekTable.entries[frameIndex].cOffset;
}
size_t ZSTD_seekable_getFrameDecompressedSize(ZSTD_seekable* const zs, U32 frameIndex)
size_t ZSTD_seekable_getFrameDecompressedSize(ZSTD_seekable* const zs, unsigned frameIndex)
{
if (frameIndex > zs->seekTable.tableLen) return ERROR(frameIndex_tooLarge);
return zs->seekTable.entries[frameIndex + 1].dOffset -
@ -447,7 +447,7 @@ size_t ZSTD_seekable_decompress(ZSTD_seekable* zs, void* dst, size_t len, unsign
return len;
}
size_t ZSTD_seekable_decompressFrame(ZSTD_seekable* zs, void* dst, size_t dstSize, U32 frameIndex)
size_t ZSTD_seekable_decompressFrame(ZSTD_seekable* zs, void* dst, size_t dstSize, unsigned frameIndex)
{
if (frameIndex >= zs->seekTable.tableLen) {
return ERROR(frameIndex_tooLarge);