/src/libzip/lib/zip_source_compress.c

Source (jump to first uncovered line)
/*
  zip_source_compress.c -- (de)compression routines
  Copyright (C) 2017-2023 Dieter Baron and Thomas Klausner

  This file is part of libzip, a library to manipulate ZIP archives.
  The authors can be contacted at <info@libzip.org>

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions
  are met:
  1. Redistributions of source code must retain the above copyright
     notice, this list of conditions and the following disclaimer.
  2. Redistributions in binary form must reproduce the above copyright
     notice, this list of conditions and the following disclaimer in
     the documentation and/or other materials provided with the
     distribution.
  3. The names of the authors may not be used to endorse or promote
     products derived from this software without specific prior
     written permission.

  THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
  OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
  IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include <stdlib.h>
#include <string.h>

#include "zipint.h"

struct context {
    zip_error_t error;

    bool end_of_input;
    bool end_of_stream;
    bool can_store;
    bool is_stored; /* only valid if end_of_stream is true */
    bool compress;
    bool check_consistency;
    zip_int32_t method;

    zip_uint64_t size;
    zip_int64_t first_read;
    zip_uint8_t buffer[BUFSIZE];

    zip_compression_algorithm_t *algorithm;
    void *ud;
};


struct implementation {
    zip_uint16_t method;
    zip_compression_algorithm_t *compress;
    zip_compression_algorithm_t *decompress;
};

static struct implementation implementations[] = {
    {ZIP_CM_DEFLATE, &zip_algorithm_deflate_compress, &zip_algorithm_deflate_decompress},
#if defined(HAVE_LIBBZ2)
    {ZIP_CM_BZIP2, &zip_algorithm_bzip2_compress, &zip_algorithm_bzip2_decompress},
#endif
#if defined(HAVE_LIBLZMA)
    {ZIP_CM_LZMA, &zip_algorithm_xz_compress, &zip_algorithm_xz_decompress},
    /*  Disabled - because 7z isn't able to unpack ZIP+LZMA2
        archives made this way - and vice versa.

        {ZIP_CM_LZMA2, &zip_algorithm_xz_compress, &zip_algorithm_xz_decompress},
    */
    {ZIP_CM_XZ, &zip_algorithm_xz_compress, &zip_algorithm_xz_decompress},
#endif
#if defined(HAVE_LIBZSTD)
    {ZIP_CM_ZSTD, &zip_algorithm_zstd_compress, &zip_algorithm_zstd_decompress},
#endif

};

static size_t implementations_size = sizeof(implementations) / sizeof(implementations[0]);

static zip_source_t *compression_source_new(zip_t *za, zip_source_t *src, zip_int32_t method, bool compress, zip_uint32_t compression_flags);
static zip_int64_t compress_callback(zip_source_t *, void *, void *, zip_uint64_t, zip_source_cmd_t);
static void context_free(struct context *ctx);
static struct context *context_new(zip_int32_t method, bool compress, zip_uint32_t compression_flags, zip_compression_algorithm_t *algorithm, bool check_consistency);
static zip_int64_t compress_read(zip_source_t *, struct context *, void *, zip_uint64_t);

zip_compression_algorithm_t *_zip_get_compression_algorithm(zip_int32_t method, bool compress) {
    size_t i;
    zip_uint16_t real_method = ZIP_CM_ACTUAL(method);

    for (i = 0; i < implementations_size; i++) {
        if (implementations[i].method == real_method) {
            if (compress) {
                return implementations[i].compress;
            }
            else {
                return implementations[i].decompress;
            }
        }
    }

    return NULL;
}

ZIP_EXTERN int zip_compression_method_supported(zip_int32_t method, int compress) {
    if (method == ZIP_CM_STORE) {
        return 1;
    }
    return _zip_get_compression_algorithm(method, compress) != NULL;
}

zip_source_t *zip_source_compress(zip_t *za, zip_source_t *src, zip_int32_t method, zip_uint32_t compression_flags) {
    return compression_source_new(za, src, method, true, compression_flags);
}

zip_source_t *
zip_source_decompress(zip_t *za, zip_source_t *src, zip_int32_t method) {
    return compression_source_new(za, src, method, false, 0);
}


static zip_source_t *compression_source_new(zip_t *za, zip_source_t *src, zip_int32_t method, bool compress, zip_uint32_t compression_flags) {
    struct context *ctx;
    zip_source_t *s2;
    zip_compression_algorithm_t *algorithm = NULL;

    if (src == NULL) {
        zip_error_set(&za->error, ZIP_ER_INVAL, 0);
        return NULL;
    }

    if ((algorithm = _zip_get_compression_algorithm(method, compress)) == NULL) {
        zip_error_set(&za->error, ZIP_ER_COMPNOTSUPP, 0);
        return NULL;
    }

    if ((ctx = context_new(method, compress, compression_flags, algorithm, za->open_flags & ZIP_CHECKCONS)) == NULL) {
        zip_error_set(&za->error, ZIP_ER_MEMORY, 0);
        return NULL;
    }

    if ((s2 = zip_source_layered(za, src, compress_callback, ctx)) == NULL) {
        context_free(ctx);
        return NULL;
    }

    return s2;
}


static struct context *context_new(zip_int32_t method, bool compress, zip_uint32_t compression_flags, zip_compression_algorithm_t *algorithm, bool check_consistency) {
    struct context *ctx;

    if ((ctx = (struct context *)malloc(sizeof(*ctx))) == NULL) {
        return NULL;
    }
    zip_error_init(&ctx->error);
    ctx->can_store = compress ? ZIP_CM_IS_DEFAULT(method) : false;
    ctx->algorithm = algorithm;
    ctx->method = method;
    ctx->compress = compress;
    ctx->end_of_input = false;
    ctx->end_of_stream = false;
    ctx->is_stored = false;
    ctx->check_consistency = check_consistency;

    if ((ctx->ud = ctx->algorithm->allocate(ZIP_CM_ACTUAL(method), compression_flags, &ctx->error)) == NULL) {
        zip_error_fini(&ctx->error);
        free(ctx);
        return NULL;
    }

    return ctx;
}


static void
context_free(struct context *ctx) {
    if (ctx == NULL) {
        return;
    }

    ctx->algorithm->deallocate(ctx->ud);
    zip_error_fini(&ctx->error);

    free(ctx);
}


static zip_int64_t
compress_read(zip_source_t *src, struct context *ctx, void *data, zip_uint64_t len) {
    zip_compression_status_t ret;
    bool end;
    zip_int64_t n;
    zip_uint64_t out_offset;
    zip_uint64_t out_len;

    if (zip_error_code_zip(&ctx->error) != ZIP_ER_OK) {
        return -1;
    }

    if (len == 0 || ctx->end_of_stream) {
        return 0;
    }

    out_offset = 0;

    end = false;
    while (!end && out_offset < len) {
        out_len = len - out_offset;
        ret = ctx->algorithm->process(ctx->ud, (zip_uint8_t *)data + out_offset, &out_len);

        if (ret != ZIP_COMPRESSION_ERROR) {
            out_offset += out_len;
        }

        switch (ret) {
        case ZIP_COMPRESSION_END:
            ctx->end_of_stream = true;

            if (!ctx->end_of_input) {
                n = zip_source_read(src, ctx->buffer, 1);
                if (n < 0) {
                    zip_error_set_from_source(&ctx->error, src);
                    end = true;
                    break;
                }
                else if (n == 0) {
                    ctx->end_of_input = true;
                    n = ctx->algorithm->end_of_input(ctx->ud) ? 1 : 0;
                }

                if (n > 0 && ctx->check_consistency) {
                    /* garbage after stream, or compression ended before all data read */
                    zip_error_set(&ctx->error, ZIP_ER_INCONS, ZIP_ER_DETAIL_COMPRESSED_DATA_TRAILING_GARBAGE);
                    end = true;
                    break;
                }
            }

            if (ctx->first_read < 0) {
                /* we got end of processed stream before reading any input data */
                zip_error_set(&ctx->error, ZIP_ER_INTERNAL, 0);
                end = true;
                break;
            }
            if (ctx->can_store && (zip_uint64_t)ctx->first_read <= out_offset) {
                ctx->is_stored = true;
                ctx->size = (zip_uint64_t)ctx->first_read;
                (void)memcpy_s(data, ctx->size, ctx->buffer, ctx->size);
                return (zip_int64_t)ctx->size;
            }
            end = true;
            break;

        case ZIP_COMPRESSION_OK:
            break;

        case ZIP_COMPRESSION_NEED_DATA:
            if (ctx->end_of_input) {
                /* TODO: error: stream not ended, but no more input */
                end = true;
                break;
            }

            if ((n = zip_source_read(src, ctx->buffer, sizeof(ctx->buffer))) < 0) {
                zip_error_set_from_source(&ctx->error, src);
                end = true;
                break;
            }
            else if (n == 0) {
                ctx->end_of_input = true;
                ctx->algorithm->end_of_input(ctx->ud);
                if (ctx->first_read < 0) {
                    ctx->first_read = 0;
                }
            }
            else {
                if (ctx->first_read >= 0) {
                    /* we overwrote a previously filled ctx->buffer */
                    ctx->can_store = false;
                }
                else {
                    ctx->first_read = n;
                }

                ctx->algorithm->input(ctx->ud, ctx->buffer, (zip_uint64_t)n);
            }
            break;

        case ZIP_COMPRESSION_ERROR:
            /* error set by algorithm */
            if (zip_error_code_zip(&ctx->error) == ZIP_ER_OK) {
                zip_error_set(&ctx->error, ZIP_ER_INTERNAL, 0);
            }
            end = true;
            break;
        }
    }

    if (out_offset > 0) {
        ctx->can_store = false;
        ctx->size += out_offset;
        return (zip_int64_t)out_offset;
    }

    return (zip_error_code_zip(&ctx->error) == ZIP_ER_OK) ? 0 : -1;
}


static zip_int64_t
compress_callback(zip_source_t *src, void *ud, void *data, zip_uint64_t len, zip_source_cmd_t cmd) {
    struct context *ctx;

    ctx = (struct context *)ud;

    switch (cmd) {
    case ZIP_SOURCE_OPEN: {
        zip_stat_t st;
        zip_file_attributes_t attributes;
        
        ctx->size = 0;
        ctx->end_of_input = false;
        ctx->end_of_stream = false;
        ctx->is_stored = false;
        ctx->first_read = -1;
        
        if (zip_source_stat(src, &st) < 0 || zip_source_get_file_attributes(src, &attributes) < 0) {
            zip_error_set_from_source(&ctx->error, src);
            return -1;
        }

        if (!ctx->algorithm->start(ctx->ud, &st, &attributes)) {
            return -1;
        }

        return 0;
    }

    case ZIP_SOURCE_READ:
        return compress_read(src, ctx, data, len);

    case ZIP_SOURCE_CLOSE:
        if (!ctx->algorithm->end(ctx->ud)) {
            return -1;
        }
        return 0;

    case ZIP_SOURCE_STAT: {
        zip_stat_t *st;

        st = (zip_stat_t *)data;

        if (ctx->compress) {
            if (ctx->end_of_stream) {
                st->comp_method = ctx->is_stored ? ZIP_CM_STORE : ZIP_CM_ACTUAL(ctx->method);
                st->comp_size = ctx->size;
                st->valid |= ZIP_STAT_COMP_SIZE | ZIP_STAT_COMP_METHOD;
            }
            else {
                st->valid &= ~(ZIP_STAT_COMP_SIZE | ZIP_STAT_COMP_METHOD);
            }
        }
        else {
            st->comp_method = ZIP_CM_STORE;
            st->valid |= ZIP_STAT_COMP_METHOD;
            st->valid &= ~ZIP_STAT_COMP_SIZE;
            if (ctx->end_of_stream) {
                st->size = ctx->size;
                st->valid |= ZIP_STAT_SIZE;
            }
        }
    }
        return 0;

    case ZIP_SOURCE_ERROR:
        return zip_error_to_data(&ctx->error, data, len);

    case ZIP_SOURCE_FREE:
        context_free(ctx);
        return 0;

    case ZIP_SOURCE_GET_FILE_ATTRIBUTES: {
        zip_file_attributes_t *attributes = (zip_file_attributes_t *)data;

        if (len < sizeof(*attributes)) {
            zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
            return -1;
        }

        attributes->valid |= ZIP_FILE_ATTRIBUTES_VERSION_NEEDED | ZIP_FILE_ATTRIBUTES_GENERAL_PURPOSE_BIT_FLAGS;
        attributes->version_needed = ctx->algorithm->version_needed;
        attributes->general_purpose_bit_mask = ZIP_FILE_ATTRIBUTES_GENERAL_PURPOSE_BIT_FLAGS_ALLOWED_MASK;
        attributes->general_purpose_bit_flags = (ctx->is_stored ? 0 : ctx->algorithm->general_purpose_bit_flags(ctx->ud));

        return sizeof(*attributes);
    }

    case ZIP_SOURCE_SUPPORTS:
        return ZIP_SOURCE_SUPPORTS_READABLE | zip_source_make_command_bitmap(ZIP_SOURCE_GET_FILE_ATTRIBUTES, ZIP_SOURCE_SUPPORTS_REOPEN, -1);

    default:
        return zip_source_pass_to_lower_layer(src, data, len, cmd);
    }
}

Coverage Report

Created: 2025-07-23 08:18

Line	Count	Source (jump to first uncovered line)
1		/*
2		zip_source_compress.c -- (de)compression routines
3		Copyright (C) 2017-2023 Dieter Baron and Thomas Klausner
4
5		This file is part of libzip, a library to manipulate ZIP archives.
6		The authors can be contacted at <info@libzip.org>
7
8		Redistribution and use in source and binary forms, with or without
9		modification, are permitted provided that the following conditions
10		are met:
11		1. Redistributions of source code must retain the above copyright
12		notice, this list of conditions and the following disclaimer.
13		2. Redistributions in binary form must reproduce the above copyright
14		notice, this list of conditions and the following disclaimer in
15		the documentation and/or other materials provided with the
16		distribution.
17		3. The names of the authors may not be used to endorse or promote
18		products derived from this software without specific prior
19		written permission.
20
21		THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
22		OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23		WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24		ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
25		DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26		DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27		GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28		INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
29		IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30		OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
31		IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32		*/
33
34		#include <stdlib.h>
35		#include <string.h>
36
37		#include "zipint.h"
38
39		struct context {
40		zip_error_t error;
41
42		bool end_of_input;
43		bool end_of_stream;
44		bool can_store;
45		bool is_stored; /* only valid if end_of_stream is true */
46		bool compress;
47		bool check_consistency;
48		zip_int32_t method;
49
50		zip_uint64_t size;
51		zip_int64_t first_read;
52		zip_uint8_t buffer[BUFSIZE];
53
54		zip_compression_algorithm_t *algorithm;
55		void *ud;
56		};
57
58
59		struct implementation {
60		zip_uint16_t method;
61		zip_compression_algorithm_t *compress;
62		zip_compression_algorithm_t *decompress;
63		};
64
65		static struct implementation implementations[] = {
66		{ZIP_CM_DEFLATE, &zip_algorithm_deflate_compress, &zip_algorithm_deflate_decompress},
67		#if defined(HAVE_LIBBZ2)
68		{ZIP_CM_BZIP2, &zip_algorithm_bzip2_compress, &zip_algorithm_bzip2_decompress},
69		#endif
70		#if defined(HAVE_LIBLZMA)
71		{ZIP_CM_LZMA, &zip_algorithm_xz_compress, &zip_algorithm_xz_decompress},
72		/* Disabled - because 7z isn't able to unpack ZIP+LZMA2
73		archives made this way - and vice versa.
74
75		{ZIP_CM_LZMA2, &zip_algorithm_xz_compress, &zip_algorithm_xz_decompress},
76		*/
77		{ZIP_CM_XZ, &zip_algorithm_xz_compress, &zip_algorithm_xz_decompress},
78		#endif
79		#if defined(HAVE_LIBZSTD)
80		{ZIP_CM_ZSTD, &zip_algorithm_zstd_compress, &zip_algorithm_zstd_decompress},
81		#endif
82
83		};
84
85		static size_t implementations_size = sizeof(implementations) / sizeof(implementations[0]);
86
87		static zip_source_t compression_source_new(zip_t za, zip_source_t *src, zip_int32_t method, bool compress, zip_uint32_t compression_flags);
88		static zip_int64_t compress_callback(zip_source_t , void , void *, zip_uint64_t, zip_source_cmd_t);
89		static void context_free(struct context *ctx);
90		static struct context context_new(zip_int32_t method, bool compress, zip_uint32_t compression_flags, zip_compression_algorithm_t algorithm, bool check_consistency);
91		static zip_int64_t compress_read(zip_source_t , struct context , void *, zip_uint64_t);
92
93	0	zip_compression_algorithm_t *_zip_get_compression_algorithm(zip_int32_t method, bool compress) {
94	0	size_t i;
95	0	zip_uint16_t real_method = ZIP_CM_ACTUAL(method);
96
97	0	for (i = 0; i < implementations_size; i++) {
98	0	if (implementations[i].method == real_method) {
99	0	if (compress) {
100	0	return implementations[i].compress;
101	0	}
102	0	else {
103	0	return implementations[i].decompress;
104	0	}
105	0	}
106	0	}
107
108	0	return NULL;
109	0	}
110
111	0	ZIP_EXTERN int zip_compression_method_supported(zip_int32_t method, int compress) {
112	0	if (method == ZIP_CM_STORE) {
113	0	return 1;
114	0	}
115	0	return _zip_get_compression_algorithm(method, compress) != NULL;
116	0	}
117
118	0	zip_source_t zip_source_compress(zip_t za, zip_source_t *src, zip_int32_t method, zip_uint32_t compression_flags) {
119	0	return compression_source_new(za, src, method, true, compression_flags);
120	0	}
121
122		zip_source_t *
123	0	zip_source_decompress(zip_t za, zip_source_t src, zip_int32_t method) {
124	0	return compression_source_new(za, src, method, false, 0);
125	0	}
126
127
128	0	static zip_source_t compression_source_new(zip_t za, zip_source_t *src, zip_int32_t method, bool compress, zip_uint32_t compression_flags) {
129	0	struct context *ctx;
130	0	zip_source_t *s2;
131	0	zip_compression_algorithm_t *algorithm = NULL;
132
133	0	if (src == NULL) {
134	0	zip_error_set(&za->error, ZIP_ER_INVAL, 0);
135	0	return NULL;
136	0	}
137
138	0	if ((algorithm = _zip_get_compression_algorithm(method, compress)) == NULL) {
139	0	zip_error_set(&za->error, ZIP_ER_COMPNOTSUPP, 0);
140	0	return NULL;
141	0	}
142
143	0	if ((ctx = context_new(method, compress, compression_flags, algorithm, za->open_flags & ZIP_CHECKCONS)) == NULL) {
144	0	zip_error_set(&za->error, ZIP_ER_MEMORY, 0);
145	0	return NULL;
146	0	}
147
148	0	if ((s2 = zip_source_layered(za, src, compress_callback, ctx)) == NULL) {
149	0	context_free(ctx);
150	0	return NULL;
151	0	}
152
153	0	return s2;
154	0	}
155
156
157	0	static struct context context_new(zip_int32_t method, bool compress, zip_uint32_t compression_flags, zip_compression_algorithm_t algorithm, bool check_consistency) {
158	0	struct context *ctx;
159
160	0	if ((ctx = (struct context )malloc(sizeof(ctx))) == NULL) {
161	0	return NULL;
162	0	}
163	0	zip_error_init(&ctx->error);
164	0	ctx->can_store = compress ? ZIP_CM_IS_DEFAULT(method) : false;
165	0	ctx->algorithm = algorithm;
166	0	ctx->method = method;
167	0	ctx->compress = compress;
168	0	ctx->end_of_input = false;
169	0	ctx->end_of_stream = false;
170	0	ctx->is_stored = false;
171	0	ctx->check_consistency = check_consistency;
172
173	0	if ((ctx->ud = ctx->algorithm->allocate(ZIP_CM_ACTUAL(method), compression_flags, &ctx->error)) == NULL) {
174	0	zip_error_fini(&ctx->error);
175	0	free(ctx);
176	0	return NULL;
177	0	}
178
179	0	return ctx;
180	0	}
181
182
183		static void
184	0	context_free(struct context *ctx) {
185	0	if (ctx == NULL) {
186	0	return;
187	0	}
188
189	0	ctx->algorithm->deallocate(ctx->ud);
190	0	zip_error_fini(&ctx->error);
191
192	0	free(ctx);
193	0	}
194
195
196		static zip_int64_t
197	0	compress_read(zip_source_t src, struct context ctx, void *data, zip_uint64_t len) {
198	0	zip_compression_status_t ret;
199	0	bool end;
200	0	zip_int64_t n;
201	0	zip_uint64_t out_offset;
202	0	zip_uint64_t out_len;
203
204	0	if (zip_error_code_zip(&ctx->error) != ZIP_ER_OK) {
205	0	return -1;
206	0	}
207
208	0	if (len == 0 \|\| ctx->end_of_stream) {
209	0	return 0;
210	0	}
211
212	0	out_offset = 0;
213
214	0	end = false;
215	0	while (!end && out_offset < len) {
216	0	out_len = len - out_offset;
217	0	ret = ctx->algorithm->process(ctx->ud, (zip_uint8_t *)data + out_offset, &out_len);
218
219	0	if (ret != ZIP_COMPRESSION_ERROR) {
220	0	out_offset += out_len;
221	0	}
222
223	0	switch (ret) {
224	0	case ZIP_COMPRESSION_END:
225	0	ctx->end_of_stream = true;
226
227	0	if (!ctx->end_of_input) {
228	0	n = zip_source_read(src, ctx->buffer, 1);
229	0	if (n < 0) {
230	0	zip_error_set_from_source(&ctx->error, src);
231	0	end = true;
232	0	break;
233	0	}
234	0	else if (n == 0) {
235	0	ctx->end_of_input = true;
236	0	n = ctx->algorithm->end_of_input(ctx->ud) ? 1 : 0;
237	0	}
238
239	0	if (n > 0 && ctx->check_consistency) {
240		/* garbage after stream, or compression ended before all data read */
241	0	zip_error_set(&ctx->error, ZIP_ER_INCONS, ZIP_ER_DETAIL_COMPRESSED_DATA_TRAILING_GARBAGE);
242	0	end = true;
243	0	break;
244	0	}
245	0	}
246
247	0	if (ctx->first_read < 0) {
248		/* we got end of processed stream before reading any input data */
249	0	zip_error_set(&ctx->error, ZIP_ER_INTERNAL, 0);
250	0	end = true;
251	0	break;
252	0	}
253	0	if (ctx->can_store && (zip_uint64_t)ctx->first_read <= out_offset) {
254	0	ctx->is_stored = true;
255	0	ctx->size = (zip_uint64_t)ctx->first_read;
256	0	(void)memcpy_s(data, ctx->size, ctx->buffer, ctx->size);
257	0	return (zip_int64_t)ctx->size;
258	0	}
259	0	end = true;
260	0	break;
261
262	0	case ZIP_COMPRESSION_OK:
263	0	break;
264
265	0	case ZIP_COMPRESSION_NEED_DATA:
266	0	if (ctx->end_of_input) {
267		/* TODO: error: stream not ended, but no more input */
268	0	end = true;
269	0	break;
270	0	}
271
272	0	if ((n = zip_source_read(src, ctx->buffer, sizeof(ctx->buffer))) < 0) {
273	0	zip_error_set_from_source(&ctx->error, src);
274	0	end = true;
275	0	break;
276	0	}
277	0	else if (n == 0) {
278	0	ctx->end_of_input = true;
279	0	ctx->algorithm->end_of_input(ctx->ud);
280	0	if (ctx->first_read < 0) {
281	0	ctx->first_read = 0;
282	0	}
283	0	}
284	0	else {
285	0	if (ctx->first_read >= 0) {
286		/* we overwrote a previously filled ctx->buffer */
287	0	ctx->can_store = false;
288	0	}
289	0	else {
290	0	ctx->first_read = n;
291	0	}
292
293	0	ctx->algorithm->input(ctx->ud, ctx->buffer, (zip_uint64_t)n);
294	0	}
295	0	break;
296
297	0	case ZIP_COMPRESSION_ERROR:
298		/* error set by algorithm */
299	0	if (zip_error_code_zip(&ctx->error) == ZIP_ER_OK) {
300	0	zip_error_set(&ctx->error, ZIP_ER_INTERNAL, 0);
301	0	}
302	0	end = true;
303	0	break;
304	0	}
305	0	}
306
307	0	if (out_offset > 0) {
308	0	ctx->can_store = false;
309	0	ctx->size += out_offset;
310	0	return (zip_int64_t)out_offset;
311	0	}
312
313	0	return (zip_error_code_zip(&ctx->error) == ZIP_ER_OK) ? 0 : -1;
314	0	}
315
316
317		static zip_int64_t
318	0	compress_callback(zip_source_t src, void ud, void *data, zip_uint64_t len, zip_source_cmd_t cmd) {
319	0	struct context *ctx;
320
321	0	ctx = (struct context *)ud;
322
323	0	switch (cmd) {
324	0	case ZIP_SOURCE_OPEN: {
325	0	zip_stat_t st;
326	0	zip_file_attributes_t attributes;
327
328	0	ctx->size = 0;
329	0	ctx->end_of_input = false;
330	0	ctx->end_of_stream = false;
331	0	ctx->is_stored = false;
332	0	ctx->first_read = -1;
333
334	0	if (zip_source_stat(src, &st) < 0 \|\| zip_source_get_file_attributes(src, &attributes) < 0) {
335	0	zip_error_set_from_source(&ctx->error, src);
336	0	return -1;
337	0	}
338
339	0	if (!ctx->algorithm->start(ctx->ud, &st, &attributes)) {
340	0	return -1;
341	0	}
342
343	0	return 0;
344	0	}
345
346	0	case ZIP_SOURCE_READ:
347	0	return compress_read(src, ctx, data, len);
348
349	0	case ZIP_SOURCE_CLOSE:
350	0	if (!ctx->algorithm->end(ctx->ud)) {
351	0	return -1;
352	0	}
353	0	return 0;
354
355	0	case ZIP_SOURCE_STAT: {
356	0	zip_stat_t *st;
357
358	0	st = (zip_stat_t *)data;
359
360	0	if (ctx->compress) {
361	0	if (ctx->end_of_stream) {
362	0	st->comp_method = ctx->is_stored ? ZIP_CM_STORE : ZIP_CM_ACTUAL(ctx->method);
363	0	st->comp_size = ctx->size;
364	0	st->valid \|= ZIP_STAT_COMP_SIZE \| ZIP_STAT_COMP_METHOD;
365	0	}
366	0	else {
367	0	st->valid &= ~(ZIP_STAT_COMP_SIZE \| ZIP_STAT_COMP_METHOD);
368	0	}
369	0	}
370	0	else {
371	0	st->comp_method = ZIP_CM_STORE;
372	0	st->valid \|= ZIP_STAT_COMP_METHOD;
373	0	st->valid &= ~ZIP_STAT_COMP_SIZE;
374	0	if (ctx->end_of_stream) {
375	0	st->size = ctx->size;
376	0	st->valid \|= ZIP_STAT_SIZE;
377	0	}
378	0	}
379	0	}
380	0	return 0;
381
382	0	case ZIP_SOURCE_ERROR:
383	0	return zip_error_to_data(&ctx->error, data, len);
384
385	0	case ZIP_SOURCE_FREE:
386	0	context_free(ctx);
387	0	return 0;
388
389	0	case ZIP_SOURCE_GET_FILE_ATTRIBUTES: {
390	0	zip_file_attributes_t attributes = (zip_file_attributes_t )data;
391
392	0	if (len < sizeof(*attributes)) {
393	0	zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
394	0	return -1;
395	0	}
396
397	0	attributes->valid \|= ZIP_FILE_ATTRIBUTES_VERSION_NEEDED \| ZIP_FILE_ATTRIBUTES_GENERAL_PURPOSE_BIT_FLAGS;
398	0	attributes->version_needed = ctx->algorithm->version_needed;
399	0	attributes->general_purpose_bit_mask = ZIP_FILE_ATTRIBUTES_GENERAL_PURPOSE_BIT_FLAGS_ALLOWED_MASK;
400	0	attributes->general_purpose_bit_flags = (ctx->is_stored ? 0 : ctx->algorithm->general_purpose_bit_flags(ctx->ud));
401
402	0	return sizeof(*attributes);
403	0	}
404
405	0	case ZIP_SOURCE_SUPPORTS:
406	0	return ZIP_SOURCE_SUPPORTS_READABLE \| zip_source_make_command_bitmap(ZIP_SOURCE_GET_FILE_ATTRIBUTES, ZIP_SOURCE_SUPPORTS_REOPEN, -1);
407
408	0	default:
409	0	return zip_source_pass_to_lower_layer(src, data, len, cmd);
410	0	}
411	0	}