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author | Dan McGee <dan@archlinux.org> | 2010-12-30 01:43:44 +0100 |
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committer | Dan McGee <dan@archlinux.org> | 2010-12-30 01:43:44 +0100 |
commit | a58083459b096e935693d94b9cb51a447b3a1abd (patch) | |
tree | e21857a8cc0b3dbe562cfe015571280c41023729 /lib/libalpm/util.c | |
parent | 126f50ab0b5ee3ed46c5a6ecae241e8af49b0fe2 (diff) | |
parent | e3c19569cfe7cd77674490b30624e71512417e0b (diff) | |
download | pacman-a58083459b096e935693d94b9cb51a447b3a1abd.tar.gz pacman-a58083459b096e935693d94b9cb51a447b3a1abd.tar.xz |
Merge branch 'fgets-perf'
Diffstat (limited to 'lib/libalpm/util.c')
-rw-r--r-- | lib/libalpm/util.c | 100 |
1 files changed, 78 insertions, 22 deletions
diff --git a/lib/libalpm/util.c b/lib/libalpm/util.c index 1291ea0f..d34eab5e 100644 --- a/lib/libalpm/util.c +++ b/lib/libalpm/util.c @@ -771,33 +771,89 @@ int _alpm_test_md5sum(const char *filepath, const char *md5sum) return(ret); } -char *_alpm_archive_fgets(char *line, size_t size, struct archive *a) +/* Note: does NOT handle sparse files on purpose for speed. */ +int _alpm_archive_fgets(struct archive *a, struct archive_read_buffer *b) { - /* for now, just read one char at a time until we get to a - * '\n' char. we can optimize this later with an internal - * buffer. */ - /* leave room for zero terminator */ - char *last = line + size - 1; - char *i; - - for(i = line; i < last; i++) { - int ret = archive_read_data(a, i, 1); - /* special check for first read- if null, return null, - * this indicates EOF */ - if(i == line && (ret <= 0 || *i == '\0')) { - return(NULL); + char *i = NULL; + int64_t offset; + int done = 0; + + while(1) { + /* have we processed this entire block? */ + if(b->block + b->block_size == b->block_offset) { + if(b->ret == ARCHIVE_EOF) { + /* reached end of archive on the last read, now we are out of data */ + goto cleanup; + } + + /* zero-copy - this is the entire next block of data. */ + b->ret = archive_read_data_block(a, (void*)&b->block, + &b->block_size, &offset); + b->block_offset = b->block; + + /* error or end of archive with no data read, cleanup */ + if(b->ret < ARCHIVE_OK || + (b->block_size == 0 && b->ret == ARCHIVE_EOF)) { + goto cleanup; + } } - /* check if read value was null or newline */ - if(ret <= 0 || *i == '\0' || *i == '\n') { - last = i + 1; - break; + + /* loop through the block looking for EOL characters */ + for(i = b->block_offset; i < (b->block + b->block_size); i++) { + /* check if read value was null or newline */ + if(*i == '\0' || *i == '\n') { + done = 1; + break; + } } - } - /* always null terminate the buffer */ - *last = '\0'; + /* allocate our buffer, or ensure our existing one is big enough */ + if(!b->line) { + /* set the initial buffer to the read block_size */ + CALLOC(b->line, b->block_size + 1, sizeof(char), + RET_ERR(PM_ERR_MEMORY, -1)); + b->line_size = b->block_size + 1; + b->line_offset = b->line; + } else { + size_t needed = (b->line_offset - b->line) + (i - b->block_offset) + 1; + if(needed > b->max_line_size) { + RET_ERR(PM_ERR_MEMORY, -1); + } + if(needed > b->line_size) { + /* need to realloc + copy data to fit total length */ + char *new; + CALLOC(new, needed, sizeof(char), RET_ERR(PM_ERR_MEMORY, -1)); + memcpy(new, b->line, b->line_size); + b->line_size = needed; + b->line_offset = new + (b->line_offset - b->line); + free(b->line); + b->line = new; + } + } + + if(done) { + size_t len = i - b->block_offset; + memcpy(b->line_offset, b->block_offset, len); + b->line_offset[len] = '\0'; + b->block_offset = ++i; + /* this is the main return point; from here you can read b->line */ + return(ARCHIVE_OK); + } else { + /* we've looked through the whole block but no newline, copy it */ + size_t len = b->block + b->block_size - b->block_offset; + memcpy(b->line_offset, b->block_offset, len); + b->line_offset += len; + b->block_offset = i; + } + } - return(line); +cleanup: + { + int ret = b->ret; + FREE(b->line); + memset(b, 0, sizeof(b)); + return(ret); + } } int _alpm_splitname(const char *target, pmpkg_t *pkg) |