diff options
author | David Seifert <soap@gentoo.org> | 2022-07-05 11:35:28 +0200 |
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committer | David Seifert <soap@gentoo.org> | 2022-07-05 11:35:28 +0200 |
commit | d98de0bb0b627772625c1acf050ba0dd4b5ac9df (patch) | |
tree | 5c4b30ab109d945fb41b2e1673ab6f8209c0f662 /src | |
parent | c3d7f491e2daebda2413fb3d2935c51df1c50ac7 (diff) | |
download | lcms2-d98de0bb0b627772625c1acf050ba0dd4b5ac9df.tar.gz |
Perform type punning via union without undefined behavior
* The previous code from c3d7f491e2daebda2413fb3d2935c51df1c50ac7
still contains undefined behavior, since it just creates
temporary pointer variables.
Diffstat (limited to 'src')
-rw-r--r-- | src/cmsplugin.c | 31 |
1 files changed, 15 insertions, 16 deletions
diff --git a/src/cmsplugin.c b/src/cmsplugin.c index 556fbc2..b34e3aa 100644 --- a/src/cmsplugin.c +++ b/src/cmsplugin.c @@ -168,22 +168,21 @@ cmsBool CMSEXPORT _cmsReadUInt32Number(cmsIOHANDLER* io, cmsUInt32Number* n) cmsBool CMSEXPORT _cmsReadFloat32Number(cmsIOHANDLER* io, cmsFloat32Number* n) { - cmsUInt32Number tmp; + union typeConverter { + cmsUInt32Number integer; + cmsFloat32Number floating_point; + } tmp; _cmsAssert(io != NULL); - if (io->Read(io, &tmp, sizeof(cmsUInt32Number), 1) != 1) + if (io->Read(io, &tmp.integer, sizeof(cmsUInt32Number), 1) != 1) return FALSE; if (n != NULL) { - const cmsFloat32Number* f; // gcc complaing on strict aliasing if this pointer is not used. - - tmp = _cmsAdjustEndianess32(tmp); + tmp.integer = _cmsAdjustEndianess32(tmp.integer); + *n = tmp.floating_point; - f = (const cmsFloat32Number*) &tmp; - *n = *f; - // Safeguard which covers against absurd values if (*n > 1E+20 || *n < -1E+20) return FALSE; @@ -309,14 +308,14 @@ cmsBool CMSEXPORT _cmsWriteUInt32Number(cmsIOHANDLER* io, cmsUInt32Number n) cmsBool CMSEXPORT _cmsWriteFloat32Number(cmsIOHANDLER* io, cmsFloat32Number n) { - cmsUInt32Number tmp; - const cmsFloat32Number* f = &n; - - _cmsAssert(io != NULL); - - tmp = *(cmsUInt32Number*)f; - tmp = _cmsAdjustEndianess32(tmp); - if (io -> Write(io, sizeof(cmsUInt32Number), &tmp) != 1) + union typeConverter { + cmsUInt32Number integer; + cmsFloat32Number floating_point; + } tmp; + + tmp.floating_point = n; + tmp.integer = _cmsAdjustEndianess32(tmp.integer); + if (io -> Write(io, sizeof(cmsUInt32Number), &tmp.integer) != 1) return FALSE; return TRUE; |