Add a ./config --solo option to make zlib subset with no libary use

A common request has been the ability to compile zlib to require no
other libraries.  This --solo option provides that ability.  The price
is that the gz*, compress*, and uncompress functions are eliminated,
and that the user must provide memory allocation and free routines to
deflate and inflate when initializing.

Makefile.in

@@ -54,11 +54,13 @@ man3dir = ${mandir}/man3
 pkgconfigdir = ${libdir}/pkgconfig
 tempfile := $(shell mktemp -u __XXXXXX)
 
-OBJC = adler32.o compress.o crc32.o deflate.o gzclose.o gzlib.o gzread.o \
+OBJZ = adler32.o crc32.o deflate.o infback.o inffast.o inflate.o inftrees.o trees.o zutil.o
-	gzwrite.o infback.o inffast.o inflate.o inftrees.o trees.o uncompr.o zutil.o
+OBJG = compress.o uncompr.o gzclose.o gzlib.o gzread.o gzwrite.o
+OBJC = $(OBJZ) $(OBJG)
 
-PIC_OBJC = adler32.lo compress.lo crc32.lo deflate.lo gzclose.lo gzlib.lo gzread.lo \
+PIC_OBJZ = adler32.lo crc32.lo deflate.lo infback.lo inffast.lo inflate.lo inftrees.lo trees.lo zutil.lo
-	gzwrite.lo infback.lo inffast.lo inflate.lo inftrees.lo trees.lo uncompr.lo zutil.lo
+PIC_OBJG = compress.lo uncompr.lo gzclose.lo gzlib.lo gzread.lo gzwrite.lo
+PIC_OBJC = $(PIC_OBJZ) $(PIC_OBJG)
 
 # to use the asm code: make OBJA=match.o, PIC_OBJA=match.lo
 OBJA =

configure

@@ -54,11 +54,14 @@ includedir=${includedir-'${prefix}/include'}
 mandir=${mandir-'${prefix}/share/man'}
 shared_ext='.so'
 shared=1
+solo=0
 zprefix=0
 build64=0
 gcc=0
 old_cc="$CC"
 old_cflags="$CFLAGS"
+OBJC='$(OBJZ) $(OBJG)'
+PIC_OBJC='$(PIC_OBJZ) $(PIC_OBJG)'
 
 while test $# -ge 1
 do
@@ -81,6 +84,7 @@ case "$1" in
     -i* | --includedir) includedir="$2"; shift; shift ;;
     -s* | --shared | --enable-shared) shared=1; shift ;;
     -t | --static) shared=0; shift ;;
+    --solo) solo=1; shift ;;
     -z* | --zprefix) zprefix=1; shift ;;
     -6* | --64) build64=1; shift ;;
     -a*=* | --archs=*) ARCHS=`echo $1 | sed 's/.*=//'`; shift ;;
@@ -331,6 +335,16 @@ if test $zprefix -eq 1; then
   echo "Using z_ prefix on all symbols."
 fi
 
+if test $solo -eq 1; then
+  sed '/#define ZCONF_H/a\
+#define Z_SOLO
+
+' < zconf.h > zconf.temp.h
+  mv zconf.temp.h zconf.h
+OBJC='$(OBJZ)'
+PIC_OBJC='$(PIC_OBJZ)'
+fi
+
 cat > $test.c <<EOF
 #include <stdio.h>
 #include <stdarg.h>
@@ -589,6 +603,8 @@ sed < Makefile.in "
 /^sharedlibdir *=/s#=.*#=$sharedlibdir#
 /^includedir *=/s#=.*#=$includedir#
 /^mandir *=/s#=.*#=$mandir#
+/^OBJC *=/s#=.*#= $OBJC#
+/^PIC_OBJC *=/s#=.*#= $PIC_OBJC#
 /^all: */s#:.*#: $ALL#
 /^test: */s#:.*#: $TEST#
 " > Makefile

deflate.c

@@ -235,10 +235,19 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
 
     strm->msg = Z_NULL;
     if (strm->zalloc == (alloc_func)0) {
+#ifdef Z_SOLO
+        return Z_STREAM_ERROR;
+#else
         strm->zalloc = zcalloc;
         strm->opaque = (voidpf)0;
+#endif
     }
-    if (strm->zfree == (free_func)0) strm->zfree = zcfree;
+    if (strm->zfree == (free_func)0)
+#ifdef Z_SOLO
+        return Z_STREAM_ERROR;
+#else
+        strm->zfree = zcfree;
+#endif
 
 #ifdef FASTEST
     if (level != 0) level = 1;
@@ -957,12 +966,12 @@ int ZEXPORT deflateCopy (dest, source)
 
     ss = source->state;
 
-    zmemcpy(dest, source, sizeof(z_stream));
+    zmemcpy((voidpf)dest, (voidpf)source, sizeof(z_stream));
 
     ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
     if (ds == Z_NULL) return Z_MEM_ERROR;
     dest->state = (struct internal_state FAR *) ds;
-    zmemcpy(ds, ss, sizeof(deflate_state));
+    zmemcpy((voidpf)ds, (voidpf)ss, sizeof(deflate_state));
     ds->strm = dest;
 
     ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
@@ -978,8 +987,8 @@ int ZEXPORT deflateCopy (dest, source)
     }
     /* following zmemcpy do not work for 16-bit MSDOS */
     zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
-    zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
+    zmemcpy((voidpf)ds->prev, (voidpf)ss->prev, ds->w_size * sizeof(Pos));
-    zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
+    zmemcpy((voidpf)ds->head, (voidpf)ss->head, ds->hash_size * sizeof(Pos));
     zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
 
     ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);

example.c

@@ -34,10 +34,6 @@ const char hello[] = "hello, hello!";
 const char dictionary[] = "hello";
 uLong dictId; /* Adler32 value of the dictionary */
 
-void test_compress      OF((Byte *compr, uLong comprLen,
-                            Byte *uncompr, uLong uncomprLen));
-void test_gzio          OF((const char *fname,
-                            Byte *uncompr, uLong uncomprLen));
 void test_deflate       OF((Byte *compr, uLong comprLen));
 void test_inflate       OF((Byte *compr, uLong comprLen,
                             Byte *uncompr, uLong uncomprLen));
@@ -53,6 +49,39 @@ void test_dict_inflate  OF((Byte *compr, uLong comprLen,
                             Byte *uncompr, uLong uncomprLen));
 int  main               OF((int argc, char *argv[]));
 
+
+#ifdef Z_SOLO
+
+void *myalloc OF((void *, unsigned, unsigned));
+void myfree OF((void *, void *));
+
+void *myalloc(q, n, m)
+    void *q;
+    unsigned n, m;
+{
+    q = Z_NULL;
+    return calloc(n, m);
+}
+
+void myfree(void *q, void *p)
+{
+    q = Z_NULL;
+    free(p);
+}
+
+static alloc_func zalloc = myalloc;
+static free_func zfree = myfree;
+
+#else /* !Z_SOLO */
+
+static alloc_func zalloc = (alloc_func)0;
+static free_func zfree = (free_func)0;
+
+void test_compress      OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_gzio          OF((const char *fname,
+                            Byte *uncompr, uLong uncomprLen));
+
 /* ===========================================================================
  * Test compress() and uncompress()
  */
@@ -163,6 +192,8 @@ void test_gzio(fname, uncompr, uncomprLen)
 #endif
 }
 
+#endif /* Z_SOLO */
+
 /* ===========================================================================
  * Test deflate() with small buffers
  */
@@ -174,8 +205,8 @@ void test_deflate(compr, comprLen)
     int err;
     uLong len = (uLong)strlen(hello)+1;
 
-    c_stream.zalloc = (alloc_func)0;
+    c_stream.zalloc = zalloc;
-    c_stream.zfree = (free_func)0;
+    c_stream.zfree = zfree;
     c_stream.opaque = (voidpf)0;
 
     err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
@@ -213,8 +244,8 @@ void test_inflate(compr, comprLen, uncompr, uncomprLen)
 
     strcpy((char*)uncompr, "garbage");
 
-    d_stream.zalloc = (alloc_func)0;
+    d_stream.zalloc = zalloc;
-    d_stream.zfree = (free_func)0;
+    d_stream.zfree = zfree;
     d_stream.opaque = (voidpf)0;
 
     d_stream.next_in  = compr;
@@ -252,8 +283,8 @@ void test_large_deflate(compr, comprLen, uncompr, uncomprLen)
     z_stream c_stream; /* compression stream */
     int err;
 
-    c_stream.zalloc = (alloc_func)0;
+    c_stream.zalloc = zalloc;
-    c_stream.zfree = (free_func)0;
+    c_stream.zfree = zfree;
     c_stream.opaque = (voidpf)0;
 
     err = deflateInit(&c_stream, Z_BEST_SPEED);
@@ -309,8 +340,8 @@ void test_large_inflate(compr, comprLen, uncompr, uncomprLen)
 
     strcpy((char*)uncompr, "garbage");
 
-    d_stream.zalloc = (alloc_func)0;
+    d_stream.zalloc = zalloc;
-    d_stream.zfree = (free_func)0;
+    d_stream.zfree = zfree;
     d_stream.opaque = (voidpf)0;
 
     d_stream.next_in  = compr;
@@ -349,8 +380,8 @@ void test_flush(compr, comprLen)
     int err;
     uInt len = (uInt)strlen(hello)+1;
 
-    c_stream.zalloc = (alloc_func)0;
+    c_stream.zalloc = zalloc;
-    c_stream.zfree = (free_func)0;
+    c_stream.zfree = zfree;
     c_stream.opaque = (voidpf)0;
 
     err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
@@ -388,8 +419,8 @@ void test_sync(compr, comprLen, uncompr, uncomprLen)
 
     strcpy((char*)uncompr, "garbage");
 
-    d_stream.zalloc = (alloc_func)0;
+    d_stream.zalloc = zalloc;
-    d_stream.zfree = (free_func)0;
+    d_stream.zfree = zfree;
     d_stream.opaque = (voidpf)0;
 
     d_stream.next_in  = compr;
@@ -430,8 +461,8 @@ void test_dict_deflate(compr, comprLen)
     z_stream c_stream; /* compression stream */
     int err;
 
-    c_stream.zalloc = (alloc_func)0;
+    c_stream.zalloc = zalloc;
-    c_stream.zfree = (free_func)0;
+    c_stream.zfree = zfree;
     c_stream.opaque = (voidpf)0;
 
     err = deflateInit(&c_stream, Z_BEST_COMPRESSION);
@@ -469,8 +500,8 @@ void test_dict_inflate(compr, comprLen, uncompr, uncomprLen)
 
     strcpy((char*)uncompr, "garbage");
 
-    d_stream.zalloc = (alloc_func)0;
+    d_stream.zalloc = zalloc;
-    d_stream.zfree = (free_func)0;
+    d_stream.zfree = zfree;
     d_stream.opaque = (voidpf)0;
 
     d_stream.next_in  = compr;
@@ -540,10 +571,15 @@ int main(argc, argv)
         printf("out of memory\n");
         exit(1);
     }
+
+#ifdef Z_SOLO
+    argc = strlen(argv[0]);
+#else
     test_compress(compr, comprLen, uncompr, uncomprLen);
 
     test_gzio((argc > 1 ? argv[1] : TESTFILE),
               uncompr, uncomprLen);
+#endif
 
     test_deflate(compr, comprLen);
     test_inflate(compr, comprLen, uncompr, uncomprLen);

infback.c

@@ -42,10 +42,19 @@ int stream_size;
         return Z_STREAM_ERROR;
     strm->msg = Z_NULL;                 /* in case we return an error */
     if (strm->zalloc == (alloc_func)0) {
+#ifdef Z_SOLO
+        return Z_STREAM_ERROR;
+#else
         strm->zalloc = zcalloc;
         strm->opaque = (voidpf)0;
+#endif
     }
-    if (strm->zfree == (free_func)0) strm->zfree = zcfree;
+    if (strm->zfree == (free_func)0)
+#ifdef Z_SOLO
+        return Z_STREAM_ERROR;
+#else
+    strm->zfree = zcfree;
+#endif
     state = (struct inflate_state FAR *)ZALLOC(strm, 1,
                                                sizeof(struct inflate_state));
     if (state == Z_NULL) return Z_MEM_ERROR;

inflate.c

@@ -180,10 +180,19 @@ int stream_size;
     if (strm == Z_NULL) return Z_STREAM_ERROR;
     strm->msg = Z_NULL;                 /* in case we return an error */
     if (strm->zalloc == (alloc_func)0) {
+#ifdef Z_SOLO
+        return Z_STREAM_ERROR;
+#else
         strm->zalloc = zcalloc;
         strm->opaque = (voidpf)0;
+#endif
     }
-    if (strm->zfree == (free_func)0) strm->zfree = zcfree;
+    if (strm->zfree == (free_func)0)
+#ifdef Z_SOLO
+        return Z_STREAM_ERROR;
+#else
+    strm->zfree = zcfree;
+#endif
     state = (struct inflate_state FAR *)
             ZALLOC(strm, 1, sizeof(struct inflate_state));
     if (state == Z_NULL) return Z_MEM_ERROR;
@@ -1433,8 +1442,8 @@ z_streamp source;
     }
 
     /* copy state */
-    zmemcpy(dest, source, sizeof(z_stream));
+    zmemcpy((voidpf)dest, (voidpf)source, sizeof(z_stream));
-    zmemcpy(copy, state, sizeof(struct inflate_state));
+    zmemcpy((voidpf)copy, (voidpf)state, sizeof(struct inflate_state));
     if (state->lencode >= state->codes &&
         state->lencode <= state->codes + ENOUGH - 1) {
         copy->lencode = copy->codes + (state->lencode - state->codes);

minigzip.c

@@ -1,5 +1,5 @@
 /* minigzip.c -- simulate gzip using the zlib compression library
- * Copyright (C) 1995-2006, 2010 Jean-loup Gailly.
+ * Copyright (C) 1995-2006, 2010, 2011 Jean-loup Gailly.
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
@@ -138,6 +138,197 @@ static void pwinerror (s)
 #  define local
 #endif
 
+#ifdef Z_SOLO
+/* for Z_SOLO, create simplified gz* functions using deflate and inflate */
+
+#if defined(Z_HAVE_UNISTD_H) || defined(Z_LARGE)
+#  include <unistd.h>       /* for unlink() */
+#endif
+
+void *myalloc OF((void *, unsigned, unsigned));
+void myfree OF((void *, void *));
+
+void *myalloc(q, n, m)
+    void *q;
+    unsigned n, m;
+{
+    q = Z_NULL;
+    return calloc(n, m);
+}
+
+void myfree(q, p)
+    void *q, *p;
+{
+    q = Z_NULL;
+    free(p);
+}
+
+typedef struct gzFile_s {
+    FILE *file;
+    int write;
+    int err;
+    char *msg;
+    z_stream strm;
+} *gzFile;
+
+gzFile gzopen OF((const char *, const char *));
+gzFile gzdopen OF((int, const char *));
+gzFile gz_open OF((const char *, int, const char *));
+
+gzFile gzopen(path, mode)
+const char *path;
+const char *mode;
+{
+    return gz_open(path, -1, mode);
+}
+
+gzFile gzdopen(fd, mode)
+int fd;
+const char *mode;
+{
+    return gz_open(NULL, fd, mode);
+}
+
+gzFile gz_open(path, fd, mode)
+    const char *path;
+    int fd;
+    const char *mode;
+{
+    gzFile gz;
+    int ret;
+
+    gz = malloc(sizeof(gzFile));
+    if (gz == NULL)
+        return NULL;
+    gz->write = strchr(mode, 'w') != NULL;
+    gz->strm.zalloc = myalloc;
+    gz->strm.zfree = myfree;
+    gz->strm.opaque = Z_NULL;
+    if (gz->write)
+        ret = deflateInit2(&(gz->strm), -1, 8, 15 + 16, 8, 0);
+    else {
+        gz->strm.next_in = 0;
+        gz->strm.avail_in = Z_NULL;
+        ret = inflateInit2(&(gz->strm), 15 + 16);
+    }
+    if (ret != Z_OK) {
+        free(gz);
+        return NULL;
+    }
+    gz->file = path == NULL ? fdopen(fd, gz->write ? "wb" : "rb") :
+                              fopen(path, gz->write ? "wb" : "rb");
+    if (gz->file == NULL) {
+        gz->write ? deflateEnd(&(gz->strm)) : inflateEnd(&(gz->strm));
+        free(gz);
+        return NULL;
+    }
+    gz->err = 0;
+    gz->msg = "";
+    return gz;
+}
+
+int gzwrite OF((gzFile, const void *, unsigned));
+
+int gzwrite(gz, buf, len)
+    gzFile gz;
+    const void *buf;
+    unsigned len;
+{
+    z_stream *strm;
+    unsigned char out[BUFLEN];
+
+    if (gz == NULL || !gz->write)
+        return 0;
+    strm = &(gz->strm);
+    strm->next_in = (void *)buf;
+    strm->avail_in = len;
+    do {
+        strm->next_out = out;
+        strm->avail_out = BUFLEN;
+        (void)deflate(strm, Z_NO_FLUSH);
+        fwrite(out, 1, BUFLEN - strm->avail_out, gz->file);
+    } while (strm->avail_out == 0);
+    return len;
+}
+
+int gzread OF((gzFile, void *, unsigned));
+
+int gzread(gz, buf, len)
+    gzFile gz;
+    void *buf;
+    unsigned len;
+{
+    int ret;
+    unsigned got;
+    unsigned char in[1];
+    z_stream *strm;
+
+    if (gz == NULL || gz->write)
+        return 0;
+    if (gz->err)
+        return 0;
+    strm = &(gz->strm);
+    strm->next_out = (void *)buf;
+    strm->avail_out = len;
+    do {
+        got = fread(in, 1, 1, gz->file);
+        if (got == 0)
+            break;
+        strm->next_in = in;
+        strm->avail_in = 1;
+        ret = inflate(strm, Z_NO_FLUSH);
+        if (ret == Z_DATA_ERROR) {
+            gz->err = Z_DATA_ERROR;
+            gz->msg = strm->msg;
+            return 0;
+        }
+        if (ret == Z_STREAM_END)
+            inflateReset(strm);
+    } while (strm->avail_out);
+    return len - strm->avail_out;
+}
+
+int gzclose OF((gzFile));
+
+int gzclose(gz)
+    gzFile gz;
+{
+    z_stream *strm;
+    unsigned char out[BUFLEN];
+
+    if (gz == NULL)
+        return Z_STREAM_ERROR;
+    strm = &(gz->strm);
+    if (gz->write) {
+        strm->next_in = Z_NULL;
+        strm->avail_in = 0;
+        do {
+            strm->next_out = out;
+            strm->avail_out = BUFLEN;
+            (void)deflate(strm, Z_FINISH);
+            fwrite(out, 1, BUFLEN - strm->avail_out, gz->file);
+        } while (strm->avail_out == 0);
+        deflateEnd(strm);
+    }
+    else
+        inflateEnd(strm);
+    fclose(gz->file);
+    free(gz);
+    return Z_OK;
+}
+
+const char *gzerror OF((gzFile, int *));
+
+const char *gzerror(gz, err)
+    gzFile gz;
+    int *err;
+{
+    *err = gz->err;
+    return gz->msg;
+}
+
+#endif
+
 char *prog;
 
 void error            OF((const char *msg));

zconf.h

@@ -28,9 +28,11 @@
 #  define adler32               z_adler32
 #  define adler32_combine       z_adler32_combine
 #  define adler32_combine64     z_adler32_combine64
+#  ifndef Z_SOLO
 #    define compress              z_compress
 #    define compress2             z_compress2
 #    define compressBound         z_compressBound
+#  endif
 #  define crc32                 z_crc32
 #  define crc32_combine         z_crc32_combine
 #  define crc32_combine64       z_crc32_combine64
@@ -49,6 +51,7 @@
 #  define deflateTune           z_deflateTune
 #  define deflate_copyright     z_deflate_copyright
 #  define get_crc_table         z_get_crc_table
+#  ifndef Z_SOLO
 #    define gz_error              z_gz_error
 #    define gz_intmax             z_gz_intmax
 #    define gz_strwinerror        z_gz_strwinerror
@@ -82,6 +85,7 @@
 #    define gztell64              z_gztell64
 #    define gzungetc              z_gzungetc
 #    define gzwrite               z_gzwrite
+#  endif
 #  define inflate               z_inflate
 #  define inflateBack           z_inflateBack
 #  define inflateBackEnd        z_inflateBackEnd
@@ -102,10 +106,14 @@
 #  define inflate_copyright     z_inflate_copyright
 #  define inflate_fast          z_inflate_fast
 #  define inflate_table         z_inflate_table
+#  ifndef Z_SOLO
 #    define uncompress            z_uncompress
+#  endif
 #  define zError                z_zError
+#  ifndef Z_SOLO
 #    define zcalloc               z_zcalloc
 #    define zcfree                z_zcfree
+#  endif
 #  define zlibCompileFlags      z_zlibCompileFlags
 #  define zlibVersion           z_zlibVersion
 
@@ -115,9 +123,11 @@
 #  define alloc_func            z_alloc_func
 #  define charf                 z_charf
 #  define free_func             z_free_func
+#  ifndef Z_SOLO
 #    define gzFile                z_gzFile
 #    define gz_header             z_gz_header
 #    define gz_headerp            z_gz_headerp
+#  endif
 #  define in_func               z_in_func
 #  define intf                  z_intf
 #  define out_func              z_out_func
@@ -130,7 +140,9 @@
 #  define voidpf                z_voidpf
 
 /* all zlib structs in zlib.h and zconf.h */
+#  ifndef Z_SOLO
 #    define gz_header_s           z_gz_header_s
+#  endif
 #  define internal_state        z_internal_state
 
 #endif
@@ -377,7 +389,9 @@ typedef uLong FAR uLongf;
 #endif
 
 #ifdef STDC
+#  ifndef Z_SOLO
 #    include <sys/types.h>      /* for off_t */
+#  endif
 #endif
 
 /* a little trick to accommodate both "#define _LARGEFILE64_SOURCE" and
@@ -394,7 +408,7 @@ typedef uLong FAR uLongf;
 #  define Z_LARGE
 #endif
 
-#if defined(Z_HAVE_UNISTD_H) || defined(Z_LARGE)
+#if (defined(Z_HAVE_UNISTD_H) || defined(Z_LARGE)) && !defined(Z_SOLO)
 #  include <unistd.h>       /* for SEEK_* and off_t */
 #  ifdef VMS
 #    include <unixio.h>     /* for off_t */
@@ -404,7 +418,7 @@ typedef uLong FAR uLongf;
 #  endif
 #endif
 
-#ifndef SEEK_SET
+#if !defined(SEEK_SET) && !defined(Z_SOLO)
 #  define SEEK_SET        0       /* Seek from beginning of file.  */
 #  define SEEK_CUR        1       /* Seek from current position.  */
 #  define SEEK_END        2       /* Set file pointer to EOF plus "offset" */

zconf.h.cmakein

@@ -30,9 +30,11 @@
 #  define adler32               z_adler32
 #  define adler32_combine       z_adler32_combine
 #  define adler32_combine64     z_adler32_combine64
+#  ifndef Z_SOLO
 #    define compress              z_compress
 #    define compress2             z_compress2
 #    define compressBound         z_compressBound
+#  endif
 #  define crc32                 z_crc32
 #  define crc32_combine         z_crc32_combine
 #  define crc32_combine64       z_crc32_combine64
@@ -51,6 +53,7 @@
 #  define deflateTune           z_deflateTune
 #  define deflate_copyright     z_deflate_copyright
 #  define get_crc_table         z_get_crc_table
+#  ifndef Z_SOLO
 #    define gz_error              z_gz_error
 #    define gz_intmax             z_gz_intmax
 #    define gz_strwinerror        z_gz_strwinerror
@@ -84,6 +87,7 @@
 #    define gztell64              z_gztell64
 #    define gzungetc              z_gzungetc
 #    define gzwrite               z_gzwrite
+#  endif
 #  define inflate               z_inflate
 #  define inflateBack           z_inflateBack
 #  define inflateBackEnd        z_inflateBackEnd
@@ -104,10 +108,14 @@
 #  define inflate_copyright     z_inflate_copyright
 #  define inflate_fast          z_inflate_fast
 #  define inflate_table         z_inflate_table
+#  ifndef Z_SOLO
 #    define uncompress            z_uncompress
+#  endif
 #  define zError                z_zError
+#  ifndef Z_SOLO
 #    define zcalloc               z_zcalloc
 #    define zcfree                z_zcfree
+#  endif
 #  define zlibCompileFlags      z_zlibCompileFlags
 #  define zlibVersion           z_zlibVersion
 
@@ -117,9 +125,11 @@
 #  define alloc_func            z_alloc_func
 #  define charf                 z_charf
 #  define free_func             z_free_func
+#  ifndef Z_SOLO
 #    define gzFile                z_gzFile
 #    define gz_header             z_gz_header
 #    define gz_headerp            z_gz_headerp
+#  endif
 #  define in_func               z_in_func
 #  define intf                  z_intf
 #  define out_func              z_out_func
@@ -132,7 +142,9 @@
 #  define voidpf                z_voidpf
 
 /* all zlib structs in zlib.h and zconf.h */
+#  ifndef Z_SOLO
 #    define gz_header_s           z_gz_header_s
+#  endif
 #  define internal_state        z_internal_state
 
 #endif
@@ -379,7 +391,9 @@ typedef uLong FAR uLongf;
 #endif
 
 #ifdef STDC
+#  ifndef Z_SOLO
 #    include <sys/types.h>      /* for off_t */
+#  endif
 #endif
 
 /* a little trick to accommodate both "#define _LARGEFILE64_SOURCE" and
@@ -396,7 +410,7 @@ typedef uLong FAR uLongf;
 #  define Z_LARGE
 #endif
 
-#if defined(Z_HAVE_UNISTD_H) || defined(Z_LARGE)
+#if (defined(Z_HAVE_UNISTD_H) || defined(Z_LARGE)) && !defined(Z_SOLO)
 #  include <unistd.h>       /* for SEEK_* and off_t */
 #  ifdef VMS
 #    include <unixio.h>     /* for off_t */
@@ -406,7 +420,7 @@ typedef uLong FAR uLongf;
 #  endif
 #endif
 
-#ifndef SEEK_SET
+#if !defined(SEEK_SET) && !defined(Z_SOLO)
 #  define SEEK_SET        0       /* Seek from beginning of file.  */
 #  define SEEK_CUR        1       /* Seek from current position.  */
 #  define SEEK_END        2       /* Set file pointer to EOF plus "offset" */

zconf.h.in

@@ -28,9 +28,11 @@
 #  define adler32               z_adler32
 #  define adler32_combine       z_adler32_combine
 #  define adler32_combine64     z_adler32_combine64
+#  ifndef Z_SOLO
 #    define compress              z_compress
 #    define compress2             z_compress2
 #    define compressBound         z_compressBound
+#  endif
 #  define crc32                 z_crc32
 #  define crc32_combine         z_crc32_combine
 #  define crc32_combine64       z_crc32_combine64
@@ -49,6 +51,7 @@
 #  define deflateTune           z_deflateTune
 #  define deflate_copyright     z_deflate_copyright
 #  define get_crc_table         z_get_crc_table
+#  ifndef Z_SOLO
 #    define gz_error              z_gz_error
 #    define gz_intmax             z_gz_intmax
 #    define gz_strwinerror        z_gz_strwinerror
@@ -82,6 +85,7 @@
 #    define gztell64              z_gztell64
 #    define gzungetc              z_gzungetc
 #    define gzwrite               z_gzwrite
+#  endif
 #  define inflate               z_inflate
 #  define inflateBack           z_inflateBack
 #  define inflateBackEnd        z_inflateBackEnd
@@ -102,10 +106,14 @@
 #  define inflate_copyright     z_inflate_copyright
 #  define inflate_fast          z_inflate_fast
 #  define inflate_table         z_inflate_table
+#  ifndef Z_SOLO
 #    define uncompress            z_uncompress
+#  endif
 #  define zError                z_zError
+#  ifndef Z_SOLO
 #    define zcalloc               z_zcalloc
 #    define zcfree                z_zcfree
+#  endif
 #  define zlibCompileFlags      z_zlibCompileFlags
 #  define zlibVersion           z_zlibVersion
 
@@ -115,9 +123,11 @@
 #  define alloc_func            z_alloc_func
 #  define charf                 z_charf
 #  define free_func             z_free_func
+#  ifndef Z_SOLO
 #    define gzFile                z_gzFile
 #    define gz_header             z_gz_header
 #    define gz_headerp            z_gz_headerp
+#  endif
 #  define in_func               z_in_func
 #  define intf                  z_intf
 #  define out_func              z_out_func
@@ -130,7 +140,9 @@
 #  define voidpf                z_voidpf
 
 /* all zlib structs in zlib.h and zconf.h */
+#  ifndef Z_SOLO
 #    define gz_header_s           z_gz_header_s
+#  endif
 #  define internal_state        z_internal_state
 
 #endif
@@ -377,7 +389,9 @@ typedef uLong FAR uLongf;
 #endif
 
 #ifdef STDC
+#  ifndef Z_SOLO
 #    include <sys/types.h>      /* for off_t */
+#  endif
 #endif
 
 /* a little trick to accommodate both "#define _LARGEFILE64_SOURCE" and
@@ -394,7 +408,7 @@ typedef uLong FAR uLongf;
 #  define Z_LARGE
 #endif
 
-#if defined(Z_HAVE_UNISTD_H) || defined(Z_LARGE)
+#if (defined(Z_HAVE_UNISTD_H) || defined(Z_LARGE)) && !defined(Z_SOLO)
 #  include <unistd.h>       /* for SEEK_* and off_t */
 #  ifdef VMS
 #    include <unixio.h>     /* for off_t */
@@ -404,7 +418,7 @@ typedef uLong FAR uLongf;
 #  endif
 #endif
 
-#ifndef SEEK_SET
+#if !defined(SEEK_SET) && !defined(Z_SOLO)
 #  define SEEK_SET        0       /* Seek from beginning of file.  */
 #  define SEEK_CUR        1       /* Seek from current position.  */
 #  define SEEK_END        2       /* Set file pointer to EOF plus "offset" */

zlib.h

@@ -1112,6 +1112,7 @@ ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
      27-31: 0 (reserved)
  */
 
+#ifndef Z_SOLO
 
                         /* utility functions */
 
@@ -1176,7 +1177,6 @@ ZEXTERN int ZEXPORT uncompress OF((Bytef *dest,   uLongf *destLen,
    buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
 */
 
-
                         /* gzip file access functions */
 
 /*
@@ -1501,6 +1501,7 @@ ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
    file that is being written concurrently.
 */
 
+#endif /* !Z_SOLO */
 
                         /* checksum functions */
 
@@ -1603,6 +1604,8 @@ ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
         inflateBackInit_((strm), (windowBits), (window), \
                       ZLIB_VERSION, (int)sizeof(z_stream))
 
+#ifndef Z_SOLO
+
 /* gzgetc() macro and its supporting function and exposed data structure.  Note
  * that the real internal state is much larger than the exposed structure.
  * This abbreviated structure exposes just enough for the gzgetc() macro.  The
@@ -1667,6 +1670,13 @@ ZEXTERN int ZEXPORT gzgetc_ OF((gzFile file));
    ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
 #endif
 
+#else /* Z_SOLO */
+
+   ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
+   ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
+
+#endif /* !Z_SOLO */
+
 /* hack for buggy compilers */
 #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
     struct internal_state {int dummy;};
@@ -1677,7 +1687,9 @@ ZEXTERN const char   * ZEXPORT zError           OF((int));
 ZEXTERN int            ZEXPORT inflateSyncPoint OF((z_streamp));
 ZEXTERN const uLongf * ZEXPORT get_crc_table    OF((void));
 ZEXTERN int            ZEXPORT inflateUndermine OF((z_streamp, int));
-ZEXTERN unsigned long  ZEXPORT gzflags          OF((void));
+#ifndef Z_SOLO
+  ZEXTERN unsigned long  ZEXPORT gzflags          OF((void));
+#endif
 
 #ifdef __cplusplus
 }

zutil.c

@@ -85,7 +85,11 @@ uLong ZEXPORT zlibCompileFlags()
 #ifdef FASTEST
     flags += 1L << 21;
 #endif
+#ifdef Z_SOLO
+    return flags;
+#else
     return flags + gzflags();
+#endif
 }
 
 #ifdef DEBUG
@@ -157,6 +161,7 @@ void ZLIB_INTERNAL zmemzero(dest, len)
 }
 #endif
 
+#ifndef Z_SOLO
 
 #ifdef SYS16BIT
 
@@ -292,3 +297,5 @@ void ZLIB_INTERNAL zcfree (opaque, ptr)
 }
 
 #endif /* MY_ZCALLOC */
+
+#endif /* !Z_SOLO */

zutil.h

@@ -21,7 +21,7 @@
 
 #include "zlib.h"
 
-#ifdef STDC
+#if defined(STDC) && !defined(Z_SOLO)
 #  if !(defined(_WIN32_WCE) && defined(_MSC_VER))
 #    include <stddef.h>
 #  endif
@@ -29,6 +29,10 @@
 #  include <stdlib.h>
 #endif
 
+#ifdef Z_SOLO
+   typedef long ptrdiff_t;  /* guess -- will be caught if guess is wrong */
+#endif
+
 #ifndef local
 #  define local static
 #endif
@@ -78,6 +82,7 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
 
 #if defined(MSDOS) || (defined(WINDOWS) && !defined(WIN32))
 #  define OS_CODE  0x00
+#  ifndef Z_SOLO
 #    if defined(__TURBOC__) || defined(__BORLANDC__)
 #      if (__STDC__ == 1) && (defined(__LARGE__) || defined(__COMPACT__))
          /* Allow compilation with ANSI keywords only enabled */
@@ -89,6 +94,7 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
 #    else /* MSC or DJGPP */
 #      include <malloc.h>
 #    endif
+#  endif
 #endif
 
 #ifdef AMIGA
@@ -107,13 +113,14 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
 
 #ifdef OS2
 #  define OS_CODE  0x06
-#  ifdef M_I86
+#  if defined(M_I86) && !defined(Z_SOLO)
 #    include <malloc.h>
 #  endif
 #endif
 
 #if defined(MACOS) || defined(TARGET_OS_MAC)
 #  define OS_CODE  0x07
+#  ifndef Z_SOLO
 #    if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
 #      include <unix.h> /* for fdopen */
 #    else
@@ -121,6 +128,7 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
 #        define fdopen(fd,mode) NULL /* No fdopen() */
 #      endif
 #    endif
+#  endif
 #endif
 
 #ifdef TOPS20
@@ -177,7 +185,7 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
 
          /* functions */
 
-#if defined(pyr)
+#if defined(pyr) || defined(Z_SOLO)
 #  define NO_MEMCPY
 #endif
 #if defined(SMALL_MEDIUM) && !defined(_MSC_VER) && !defined(__SC__)
@@ -226,10 +234,11 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
 #  define Tracecv(c,x)
 #endif
 
-
+#ifndef Z_SOLO
-voidpf ZLIB_INTERNAL zcalloc OF((voidpf opaque, unsigned items,
+   voidpf ZLIB_INTERNAL zcalloc OF((voidpf opaque, unsigned items,
                                     unsigned size));
-void ZLIB_INTERNAL zcfree  OF((voidpf opaque, voidpf ptr));
+   void ZLIB_INTERNAL zcfree  OF((voidpf opaque, voidpf ptr));
+#endif
 
 #define ZALLOC(strm, items, size) \
            (*((strm)->zalloc))((strm)->opaque, (items), (size))