chromium/third_party/zlib/gzwrite.c

/* gzwrite.c -- zlib functions for writing gzip files
 * Copyright (C) 2004-2019 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

#include "gzguts.h"

/* 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(gz_statep state) { … }

/* 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(gz_statep state, int flush) { … }

/* 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(gz_statep state, z_off64_t len) { … }

/* Write len bytes from buf to file.  Return the number of bytes written.  If
   the returned value is less than len, then there was an error. */
local z_size_t gz_write(gz_statep state, voidpc buf, z_size_t len) { … }

/* -- see zlib.h -- */
int ZEXPORT gzwrite(gzFile file, voidpc buf, unsigned len) { … }

/* -- see zlib.h -- */
z_size_t ZEXPORT gzfwrite(voidpc buf, z_size_t size, z_size_t nitems,
                          gzFile file) { … }

/* -- see zlib.h -- */
int ZEXPORT gzputc(gzFile file, int c) { … }

/* -- see zlib.h -- */
int ZEXPORT gzputs(gzFile file, const char *s) { … }

#if defined(STDC) || defined(Z_HAVE_STDARG_H)
#include <stdarg.h>

/* -- see zlib.h -- */
int ZEXPORTVA gzvprintf(gzFile file, const char *format, va_list va) { … }

int ZEXPORTVA gzprintf(gzFile file, const char *format, ...) { … }

#else /* !STDC && !Z_HAVE_STDARG_H */

/* -- see zlib.h -- */
int ZEXPORTVA gzprintf(gzFile file, const char *format, int a1, int a2, int a3,
                       int a4, int a5, int a6, int a7, int a8, int a9, int a10,
                       int a11, int a12, int a13, int a14, int a15, int a16,
                       int a17, int a18, int a19, int a20) {
    unsigned len, left;
    char *next;
    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 can really pass pointer in ints */
    if (sizeof(int) != sizeof(void *))
        return Z_STREAM_ERROR;

    /* check that we're writing and that there's no error */
    if (state->mode != GZ_WRITE || state->err != Z_OK)
        return Z_STREAM_ERROR;

    /* make sure we have some buffer space */
    if (state->size == 0 && gz_init(state) == -1)
        return state->error;

    /* check for seek request */
    if (state->seek) {
        state->seek = 0;
        if (gz_zero(state, state->skip) == -1)
            return state->error;
    }

    /* do the printf() into the input buffer, put length in len -- the input
       buffer is double-sized just for this function, so there is guaranteed to
       be state->size bytes available after the current contents */
    if (strm->avail_in == 0)
        strm->next_in = state->in;
    next = (char *)(strm->next_in + strm->avail_in);
    next[state->size - 1] = 0;
#ifdef NO_snprintf
#  ifdef HAS_sprintf_void
    sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12,
            a13, a14, a15, a16, a17, a18, a19, a20);
    for (len = 0; len < size; len++)
        if (next[len] == 0)
            break;
#  else
    len = sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11,
                  a12, a13, a14, a15, a16, a17, a18, a19, a20);
#  endif
#else
#  ifdef HAS_snprintf_void
    snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8, a9,
             a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
    len = strlen(next);
#  else
    len = snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8,
                   a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
#  endif
#endif

    /* check that printf() results fit in buffer */
    if (len == 0 || len >= state->size || next[state->size - 1] != 0)
        return 0;

    /* update buffer and position, compress first half if past that */
    strm->avail_in += len;
    state->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;
        memmove(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(gzFile file, int flush) { … }

/* -- see zlib.h -- */
int ZEXPORT gzsetparams(gzFile file, int level, int strategy) { … }

/* -- see zlib.h -- */
int ZEXPORT gzclose_w(gzFile file) { … }