/* gzwrite.c -- zlib functions for writing gzip files * Copyright (C) 2004-2017 Mark Adler * For conditions of distribution and use, see copyright notice in zlib.h */ #include "gzguts.h" /* Local functions */ local int gz_init OF((gz_statep)); local int gz_comp OF((gz_statep, int)); local int gz_zero OF((gz_statep, z_off64_t)); local z_size_t gz_write OF((gz_statep, voidpc, z_size_t)); /* Initialize state for writing a gzip file. Mark initialization by setting state->size to non-zero. Return -1 on a memory allocation failure, or 0 on success. */ local int gz_init(state) gz_statep state; { int ret; z_streamp strm = &(state->strm); /* allocate input buffer (double size for gzprintf) */ state->in = (unsigned char *)malloc(state->want << 1); if (state->in == NULL) { gz_error(state, Z_MEM_ERROR, "out of memory"); return -1; } /* only need output buffer and deflate state if compressing */ if (!state->direct) { /* allocate output buffer */ state->out = (unsigned char *)malloc(state->want); if (state->out == NULL) { free(state->in); gz_error(state, Z_MEM_ERROR, "out of memory"); return -1; } /* allocate deflate memory, set up for gzip compression */ strm->zalloc = Z_NULL; strm->zfree = Z_NULL; strm->opaque = Z_NULL; ret = deflateInit2(strm, state->level, Z_DEFLATED, MAX_WBITS + 16, DEF_MEM_LEVEL, state->strategy); if (ret != Z_OK) { free(state->out); free(state->in); gz_error(state, Z_MEM_ERROR, "out of memory"); return -1; } strm->next_in = NULL; } /* mark state as initialized */ state->size = state->want; /* initialize write buffer if compressing */ if (!state->direct) { strm->avail_out = state->size; strm->next_out = state->out; state->x.next = strm->next_out; } return 0; } /* Compress whatever is at avail_in and next_in and write to the output file. Return -1 if there is an error writing to the output file or if gz_init() fails to allocate memory, otherwise 0. flush is assumed to be a valid deflate() flush value. If flush is Z_FINISH, then the deflate() state is reset to start a new gzip stream. If gz->direct is true, then simply write to the output file without compressing, and ignore flush. */ local int gz_comp(state, flush) gz_statep state; int flush; { int ret, writ; unsigned have, put, max = ((unsigned)-1 >> 2) + 1; z_streamp strm = &(state->strm); /* allocate memory if this is the first time through */ if (state->size == 0 && gz_init(state) == -1) return -1; /* write directly if requested */ if (state->direct) { while (strm->avail_in) { put = strm->avail_in > max ? max : strm->avail_in; writ = write(state->fd, strm->next_in, put); if (writ < 0) { gz_error(state, Z_ERRNO, zstrerror()); return -1; } strm->avail_in -= (unsigned)writ; strm->next_in += writ; } return 0; } /* run deflate() on provided input until it produces no more output */ ret = Z_OK; do { /* write out current buffer contents if full, or if flushing, but if doing Z_FINISH then don't write until we get to Z_STREAM_END */ if (strm->avail_out == 0 || (flush != Z_NO_FLUSH && (flush != Z_FINISH || ret == Z_STREAM_END))) { while (strm->next_out > state->x.next) { put = strm->next_out - state->x.next > (int)max ? max : (unsigned)(strm->next_out - state->x.next); writ = write(state->fd, state->x.next, put); if (writ < 0) { gz_error(state, Z_ERRNO, zstrerror()); return -1; } state->x.next += writ; } if (strm->avail_out == 0) { strm->avail_out = state->size; strm->next_out = state->out; state->x.next = state->out; } } /* compress */ have = strm->avail_out; ret = deflate(strm, flush); if (ret == Z_STREAM_ERROR) { gz_error(state, Z_STREAM_ERROR, "internal error: deflate stream corrupt"); return -1; } have -= strm->avail_out; } while (have); /* if that completed a deflate stream, allow another to start */ if (flush == Z_FINISH) deflateReset(strm); /* all done, no errors */ return 0; } /* Compress len zeros to output. Return -1 on a write error or memory allocation failure by gz_comp(), or 0 on success. */ local int gz_zero(state, len) gz_statep state; z_off64_t len; { int first; unsigned n; z_streamp strm = &(state->strm); /* consume whatever's left in the input buffer */ if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1) return -1; /* compress len zeros (len guaranteed > 0) */ first = 1; while (len) { n = GT_OFF(state->size) || (z_off64_t)state->size > len ? (unsigned)len : state->size; if (first) { memset(state->in, 0, n); first = 0; } strm->avail_in = n; strm->next_in = state->in; state->x.pos += n; if (gz_comp(state, Z_NO_FLUSH) == 
/* inftrees.h -- header to use inftrees.c
 * Copyright (C) 1995-2005, 2010 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

/* WARNING: this file should *not* be used by applications. It is
   part of the implementation of the compression library and is
   subject to change. Applications should only use zlib.h.
 */

/* Structure for decoding tables.  Each entry provides either the
   information needed to do the operation requested by the code that
   indexed that table entry, or it provides a pointer to another
   table that indexes more bits of the code.  op indicates whether
   the entry is a pointer to another table, a literal, a length or
   distance, an end-of-block, or an invalid code.  For a table
   pointer, the low four bits of op is the number of index bits of
   that table.  For a length or distance, the low four bits of op
   is the number of extra bits to get after the code.  bits is
   the number of bits in this code or part of the code to drop off
   of the bit buffer.  val is the actual byte to output in the case
   of a literal, the base length or distance, or the offset from
   the current table to the next table.  Each entry is four bytes. */
typedef struct {
    unsigned char op;           /* operation, extra bits, table bits */
    unsigned char bits;         /* bits in this part of the code */
    unsigned short val;         /* offset in table or code value */
} code;

/* op values as set by inflate_table():
    00000000 - literal
    0000tttt - table link, tttt != 0 is the number of table index bits
    0001eeee - length or distance, eeee is the number of extra bits
    01100000 - end of block
    01000000 - invalid code
 */

/* Maximum size of the dynamic table.  The maximum number of code structures is
   1444, which is the sum of 852 for literal/length codes and 592 for distance
   codes.  These values were found by exhaustive searches using the program
   examples/enough.c found in the zlib distribtution.  The arguments to that
   program are the number of symbols, the initial root table size, and the
   maximum bit length of a code.  "enough 286 9 15" for literal/length codes
   returns returns 852, and "enough 30 6 15" for distance codes returns 592.
   The initial root table size (9 or 6) is found in the fifth argument of the
   inflate_table() calls in inflate.c and infback.c.  If the root table size is
   changed, then these maximum sizes would be need to be recalculated and
   updated. */
#define ENOUGH_LENS 852
#define ENOUGH_DISTS 592
#define ENOUGH (ENOUGH_LENS+ENOUGH_DISTS)

/* Type of code to build for inflate_table() */
typedef enum {
    CODES,
    LENS,
    DISTS
} codetype;

int ZLIB_INTERNAL inflate_table OF((codetype type, unsigned short FAR *lens,
                             unsigned codes, code FAR * FAR *table,
                             unsigned FAR *bits, unsigned short FAR *work));
>x.pos += len; if (strm->avail_in >= state->size) { left = strm->avail_in - state->size; strm->avail_in = state->size; if (gz_comp(state, Z_NO_FLUSH) == -1) return state->err; memcpy(state->in, state->in + state->size, left); strm->next_in = state->in; strm->avail_in = left; } return (int)len; } #endif /* -- see zlib.h -- */ int ZEXPORT gzflush(file, flush) gzFile file; int flush; { gz_statep state; /* get internal structure */ if (file == NULL) return Z_STREAM_ERROR; state = (gz_statep)file; /* check that we're writing and that there's no error */ if (state->mode != GZ_WRITE || state->err != Z_OK) return Z_STREAM_ERROR; /* check flush parameter */ if (flush < 0 || flush > Z_FINISH) return Z_STREAM_ERROR; /* check for seek request */ if (state->seek) { state->seek = 0; if (gz_zero(state, state->skip) == -1) return state->err; } /* compress remaining data with requested flush */ (void)gz_comp(state, flush); return state->err; } /* -- see zlib.h -- */ int ZEXPORT gzsetparams(file, level, strategy) gzFile file; int level; int strategy; { gz_statep state; z_streamp strm; /* get internal structure */ if (file == NULL) return Z_STREAM_ERROR; state = (gz_statep)file; strm = &(state->strm); /* check that we're writing and that there's no error */ if (state->mode != GZ_WRITE || state->err != Z_OK) return Z_STREAM_ERROR; /* if no change is requested, then do nothing */ if (level == state->level && strategy == state->strategy) return Z_OK; /* check for seek request */ if (state->seek) { state->seek = 0; if (gz_zero(state, state->skip) == -1) return state->err; } /* change compression parameters for subsequent input */ if (state->size) { /* flush previous input with previous parameters before changing */ if (strm->avail_in && gz_comp(state, Z_BLOCK) == -1) return state->err; deflateParams(strm, level, strategy); } state->level = level; state->strategy = strategy; return Z_OK; } /* -- see zlib.h -- */ int ZEXPORT gzclose_w(file) gzFile file; { int ret = Z_OK; gz_statep state; /* get internal structure */ if (file == NULL) return Z_STREAM_ERROR; state = (gz_statep)file; /* check that we're writing */ if (state->mode != GZ_WRITE) return Z_STREAM_ERROR; /* check for seek request */ if (state->seek) { state->seek = 0; if (gz_zero(state, state->skip) == -1) ret = state->err; } /* flush, free memory, and close file */ if (gz_comp(state, Z_FINISH) == -1) ret = state->err; if (state->size) { if (!state->direct) { (void)deflateEnd(&(state->strm)); free(state->out); } free(state->in); } gz_error(state, Z_OK, NULL); free(state->path); if (close(state->fd) == -1) ret = Z_ERRNO; free(state); return ret; }