Change gzgetc() to a macro for speed (~40% speedup in testing).

This commit is contained in:
Mark Adler
2011-09-26 22:50:28 -07:00
parent 8e0d212910
commit acfc85772a
5 changed files with 119 additions and 91 deletions

38
gzlib.c
View File

@@ -71,15 +71,15 @@ char ZLIB_INTERNAL *gz_strwinerror (error)
local void gz_reset(state)
gz_statep state;
{
state->x.have = 0; /* no output data available */
if (state->mode == GZ_READ) { /* for reading ... */
state->have = 0; /* no output data available */
state->eof = 0; /* not at end of file */
state->how = LOOK; /* look for gzip header */
state->direct = 1; /* default for empty file */
}
state->seek = 0; /* no seek request pending */
gz_error(state, Z_OK, NULL); /* clear error */
state->pos = 0; /* no uncompressed data yet */
state->x.pos = 0; /* no uncompressed data yet */
state->strm.avail_in = 0; /* no input data yet */
}
@@ -303,31 +303,31 @@ z_off64_t ZEXPORT gzseek64(file, offset, whence)
/* normalize offset to a SEEK_CUR specification */
if (whence == SEEK_SET)
offset -= state->pos;
offset -= state->x.pos;
else if (state->seek)
offset += state->skip;
state->seek = 0;
/* if within raw area while reading, just go there */
if (state->mode == GZ_READ && state->how == COPY &&
state->pos + offset >= 0) {
ret = LSEEK(state->fd, offset - state->have, SEEK_CUR);
state->x.pos + offset >= 0) {
ret = LSEEK(state->fd, offset - state->x.have, SEEK_CUR);
if (ret == -1)
return -1;
state->have = 0;
state->x.have = 0;
state->eof = 0;
state->seek = 0;
gz_error(state, Z_OK, NULL);
state->strm.avail_in = 0;
state->pos += offset;
return state->pos;
state->x.pos += offset;
return state->x.pos;
}
/* calculate skip amount, rewinding if needed for back seek when reading */
if (offset < 0) {
if (state->mode != GZ_READ) /* writing -- can't go backwards */
return -1;
offset += state->pos;
offset += state->x.pos;
if (offset < 0) /* before start of file! */
return -1;
if (gzrewind(file) == -1) /* rewind, then skip to offset */
@@ -336,11 +336,11 @@ z_off64_t ZEXPORT gzseek64(file, offset, whence)
/* if reading, skip what's in output buffer (one less gzgetc() check) */
if (state->mode == GZ_READ) {
n = GT_OFF(state->have) || (z_off64_t)state->have > offset ?
(unsigned)offset : state->have;
state->have -= n;
state->next += n;
state->pos += n;
n = GT_OFF(state->x.have) || (z_off64_t)state->x.have > offset ?
(unsigned)offset : state->x.have;
state->x.have -= n;
state->x.next += n;
state->x.pos += n;
offset -= n;
}
@@ -349,7 +349,7 @@ z_off64_t ZEXPORT gzseek64(file, offset, whence)
state->seek = 1;
state->skip = offset;
}
return state->pos + offset;
return state->x.pos + offset;
}
/* -- see zlib.h -- */
@@ -378,7 +378,7 @@ z_off64_t ZEXPORT gztell64(file)
return -1;
/* return position */
return state->pos + (state->seek ? state->skip : 0);
return state->x.pos + (state->seek ? state->skip : 0);
}
/* -- see zlib.h -- */
@@ -439,7 +439,7 @@ int ZEXPORT gzeof(file)
/* return end-of-file state */
return state->mode == GZ_READ ?
(state->eof && state->strm.avail_in == 0 && state->have == 0) : 0;
(state->eof && state->strm.avail_in == 0 && state->x.have == 0) : 0;
}
/* -- see zlib.h -- */
@@ -499,6 +499,10 @@ void ZLIB_INTERNAL gz_error(state, err, msg)
state->msg = NULL;
}
/* if fatal, set state->x.have to 0 so that the gzgetc() macro fails */
if (err != Z_OK && err != Z_BUF_ERROR)
state->x.have = 0;
/* set error code, and if no message, then done */
state->err = err;
if (msg == NULL)