/src/libzip/lib/zip_source_file_common.c

Source
/*
  zip_source_file_common.c -- create data source from file
  Copyright (C) 1999-2025 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 "zipint.h"

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

#include "zip_source_file.h"

static zip_int64_t read_file(void *state, void *data, zip_uint64_t len, zip_source_cmd_t cmd);

static void zip_source_file_stat_init(zip_source_file_stat_t *st) {
    st->size = 0;
    st->mtime = time(NULL);
    st->exists = false;
    st->regular_file = false;
}

zip_source_t *zip_source_file_common_new(const char *fname, void *file, zip_uint64_t start, zip_int64_t len, const zip_stat_t *st, zip_source_file_operations_t *ops, void *ops_userdata, zip_error_t *error) {
    zip_source_file_context_t *ctx;
    zip_source_t *zs;
    zip_source_file_stat_t sb;
    zip_uint64_t length;

    if (ops == NULL) {
        zip_error_set(error, ZIP_ER_INVAL, 0);
        return NULL;
    }

    if (ops->close == NULL || ops->read == NULL || ops->seek == NULL || ops->stat == NULL) {
        zip_error_set(error, ZIP_ER_INTERNAL, 0);
        return NULL;
    }

    if (ops->write != NULL && (ops->commit_write == NULL || ops->create_temp_output == NULL || ops->remove == NULL || ops->rollback_write == NULL || ops->tell == NULL)) {
        zip_error_set(error, ZIP_ER_INTERNAL, 0);
        return NULL;
    }

    if (fname != NULL) {
        if (ops->open == NULL || ops->string_duplicate == NULL) {
            zip_error_set(error, ZIP_ER_INTERNAL, 0);
            return NULL;
        }
    }
    else if (file == NULL) {
        zip_error_set(error, ZIP_ER_INVAL, 0);
        return NULL;
    }

    if (len < 0) {
        if (len == -1) {
            len = ZIP_LENGTH_TO_END;
        }
        // TODO: return ZIP_ER_INVAL if len != ZIP_LENGTH_UNCHECKED?
        length = 0;
    }
    else {
        length = (zip_uint64_t)len;
    }

    if (start > ZIP_INT64_MAX || start + length < start) {
        zip_error_set(error, ZIP_ER_INVAL, 0);
        return NULL;
    }

    if ((ctx = (zip_source_file_context_t *)malloc(sizeof(zip_source_file_context_t))) == NULL) {
        zip_error_set(error, ZIP_ER_MEMORY, 0);
        return NULL;
    }

    ctx->ops = ops;
    ctx->ops_userdata = ops_userdata;
    ctx->fname = NULL;
    if (fname) {
        if ((ctx->fname = ops->string_duplicate(ctx, fname)) == NULL) {
            zip_error_set(error, ZIP_ER_MEMORY, 0);
            free(ctx);
            return NULL;
        }
    }
    ctx->f = file;
    ctx->start = start;
    ctx->len = length;
    if (st) {
        (void)memcpy_s(&ctx->st, sizeof(ctx->st), st, sizeof(*st));
        ctx->st.name = NULL;
        ctx->st.valid &= ~ZIP_STAT_NAME;
    }
    else {
        zip_stat_init(&ctx->st);
    }

    if (ctx->len > 0) {
        ctx->st.size = ctx->len;
        ctx->st.valid |= ZIP_STAT_SIZE;
    }

    zip_error_init(&ctx->stat_error);

    ctx->tmpname = NULL;
    ctx->fout = NULL;

    zip_error_init(&ctx->error);
    zip_file_attributes_init(&ctx->attributes);

    ctx->supports = ZIP_SOURCE_SUPPORTS_READABLE | zip_source_make_command_bitmap(ZIP_SOURCE_SUPPORTS, ZIP_SOURCE_TELL, ZIP_SOURCE_SUPPORTS_REOPEN, -1);

    zip_source_file_stat_init(&sb);
    if (!ops->stat(ctx, &sb)) {
        _zip_error_copy(error, &ctx->error);
        free(ctx->fname);
        free(ctx);
        return NULL;
    }

    if (!sb.exists) {
        if (ctx->fname && ctx->start == 0 && ctx->len == 0 && ops->write != NULL) {
            ctx->supports = ZIP_SOURCE_SUPPORTS_WRITABLE;
            /* zip_open_from_source checks for this to detect non-existing files */
            zip_error_set(&ctx->stat_error, ZIP_ER_READ, ENOENT);
        }
        else {
            zip_error_set(&ctx->stat_error, ZIP_ER_READ, ENOENT);
            free(ctx->fname);
            free(ctx);
            return NULL;
        }
    }
    else {
        if ((ctx->st.valid & ZIP_STAT_MTIME) == 0) {
            ctx->st.mtime = sb.mtime;
            ctx->st.valid |= ZIP_STAT_MTIME;
        }
        if (sb.regular_file) {
            ctx->supports = ZIP_SOURCE_SUPPORTS_SEEKABLE;

            if (ctx->start + ctx->len > sb.size) {
                zip_error_set(error, ZIP_ER_INVAL, 0);
                free(ctx->fname);
                free(ctx);
                return NULL;
            }

            if (ctx->len == 0) {
                if (len != ZIP_LENGTH_UNCHECKED) {
                    ctx->len = sb.size - ctx->start;
                    ctx->st.size = ctx->len;
                    ctx->st.valid |= ZIP_STAT_SIZE;
                }

                /* when using a partial file, don't allow writing */
                if (ctx->fname && start == 0 && ops->write != NULL) {
                    ctx->supports = ZIP_SOURCE_SUPPORTS_WRITABLE;
                }
            }
        }

        if (ctx->st.valid & ZIP_STAT_SIZE) {
            ctx->supports |= ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_AT_EOF);
        }

        ctx->supports |= ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_GET_FILE_ATTRIBUTES);
    }

    ctx->supports |= ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_ACCEPT_EMPTY);
    if (ops->create_temp_output_cloning != NULL) {
        if (ctx->supports & ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_BEGIN_WRITE)) {
            ctx->supports |= ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_BEGIN_WRITE_CLONING);
        }
    }

    if ((zs = zip_source_function_create(read_file, ctx, error)) == NULL) {
        free(ctx->fname);
        free(ctx);
        return NULL;
    }

    return zs;
}


static zip_int64_t read_file(void *state, void *data, zip_uint64_t len, zip_source_cmd_t cmd) {
    zip_source_file_context_t *ctx;
    char *buf;

    ctx = (zip_source_file_context_t *)state;
    buf = (char *)data;

    switch (cmd) {
    case ZIP_SOURCE_ACCEPT_EMPTY:
        return 0;

    case ZIP_SOURCE_AT_EOF:
        /* We only advertise support for ZIP_SOURCE_AT_EOF if ctx->len is valid. */
        return ctx->offset == ctx->len;

    case ZIP_SOURCE_BEGIN_WRITE: {
        zip_int64_t ret;
        /* write support should not be set if fname is NULL */
        if (ctx->fname == NULL) {
            zip_error_set(&ctx->error, ZIP_ER_INTERNAL, 0);
            return -1;
        }
        ret = ctx->ops->create_temp_output(ctx);
        if (ret == 0) {
            /* Clear past error. Otherwise the error from zip_source_begin_write_cloning() will persist and be reported on zip_source_close(). */
            zip_error_set(&ctx->error, ZIP_ER_OK, 0);
        }
        return ret;
    }

    case ZIP_SOURCE_BEGIN_WRITE_CLONING:
        /* write support should not be set if fname is NULL */
        if (ctx->fname == NULL) {
            zip_error_set(&ctx->error, ZIP_ER_INTERNAL, 0);
            return -1;
        }
        return ctx->ops->create_temp_output_cloning(ctx, len);

    case ZIP_SOURCE_CLOSE:
        if (ctx->fname) {
            ctx->ops->close(ctx);
            ctx->f = NULL;
        }
        return 0;

    case ZIP_SOURCE_COMMIT_WRITE: {
        zip_int64_t ret = ctx->ops->commit_write(ctx);
        ctx->fout = NULL;
        if (ret == 0) {
            free(ctx->tmpname);
            ctx->tmpname = NULL;
        }
        return ret;
    }

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

    case ZIP_SOURCE_FREE:
        free(ctx->fname);
        free(ctx->tmpname);
        if (ctx->f) {
            ctx->ops->close(ctx);
        }
        free(ctx);
        return 0;

    case ZIP_SOURCE_GET_FILE_ATTRIBUTES:
        if (len < sizeof(ctx->attributes)) {
            zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
            return -1;
        }
        (void)memcpy_s(data, sizeof(ctx->attributes), &ctx->attributes, sizeof(ctx->attributes));
        return sizeof(ctx->attributes);

    case ZIP_SOURCE_OPEN:
        if (ctx->fname) {
            if (ctx->ops->open(ctx) == false) {
                return -1;
            }
        }

        if (ctx->start > 0) { /* TODO: rewind on re-open */
            if (ctx->ops->seek(ctx, ctx->f, (zip_int64_t)ctx->start, SEEK_SET) == false) {
                /* TODO: skip by reading */
                return -1;
            }
        }
        ctx->offset = 0;
        return 0;

    case ZIP_SOURCE_READ: {
        zip_int64_t i;
        zip_uint64_t n;

        if (ctx->len > 0) {
            n = ZIP_MIN(ctx->len - ctx->offset, len);
        }
        else {
            n = len;
        }

        if ((i = ctx->ops->read(ctx, buf, n)) < 0) {
            zip_error_set(&ctx->error, ZIP_ER_READ, errno);
            return -1;
        }
        ctx->offset += (zip_uint64_t)i;

        return i;
    }

    case ZIP_SOURCE_REMOVE:
        return ctx->ops->remove(ctx);

    case ZIP_SOURCE_ROLLBACK_WRITE:
        ctx->ops->rollback_write(ctx);
        ctx->fout = NULL;
        free(ctx->tmpname);
        ctx->tmpname = NULL;
        return 0;

    case ZIP_SOURCE_SEEK: {
        zip_int64_t new_offset = zip_source_seek_compute_offset(ctx->offset, ctx->len, data, len, &ctx->error);

        if (new_offset < 0) {
            return -1;
        }

        /* The actual offset inside the file must be representable as zip_int64_t. */
        if (new_offset > ZIP_INT64_MAX - (zip_int64_t)ctx->start) {
            zip_error_set(&ctx->error, ZIP_ER_SEEK, EOVERFLOW);
            return -1;
        }

        ctx->offset = (zip_uint64_t)new_offset;

        if (ctx->ops->seek(ctx, ctx->f, (zip_int64_t)(ctx->offset + ctx->start), SEEK_SET) == false) {
            return -1;
        }
        return 0;
    }

    case ZIP_SOURCE_SEEK_WRITE: {
        zip_source_args_seek_t *args;

        args = ZIP_SOURCE_GET_ARGS(zip_source_args_seek_t, data, len, &ctx->error);
        if (args == NULL) {
            return -1;
        }

        if (ctx->ops->seek(ctx, ctx->fout, args->offset, args->whence) == false) {
            return -1;
        }
        return 0;
    }

    case ZIP_SOURCE_STAT: {
        if (len < sizeof(ctx->st)) {
            return -1;
        }

        if (zip_error_code_zip(&ctx->stat_error) != 0) {
            zip_error_set(&ctx->error, zip_error_code_zip(&ctx->stat_error), zip_error_code_system(&ctx->stat_error));
            return -1;
        }

        (void)memcpy_s(data, sizeof(ctx->st), &ctx->st, sizeof(ctx->st));
        return sizeof(ctx->st);
    }

    case ZIP_SOURCE_SUPPORTS:
        return ctx->supports;

    case ZIP_SOURCE_TELL:
        return (zip_int64_t)ctx->offset;

    case ZIP_SOURCE_TELL_WRITE:
        return ctx->ops->tell(ctx, ctx->fout);

    case ZIP_SOURCE_WRITE:
        return ctx->ops->write(ctx, data, len);

    default:
        zip_error_set(&ctx->error, ZIP_ER_OPNOTSUPP, 0);
        return -1;
    }
}

Coverage Report

Created: 2026-07-25 07:06

Line	Count	Source
1		/*
2		zip_source_file_common.c -- create data source from file
3		Copyright (C) 1999-2025 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 "zipint.h"
35
36		#include <stdio.h>
37		#include <stdlib.h>
38		#include <string.h>
39
40		#include "zip_source_file.h"
41
42		static zip_int64_t read_file(void state, void data, zip_uint64_t len, zip_source_cmd_t cmd);
43
44	25	static void zip_source_file_stat_init(zip_source_file_stat_t *st) {
45	25	st->size = 0;
46	25	st->mtime = time(NULL);
47	25	st->exists = false;
48	25	st->regular_file = false;
49	25	}
50
51	25	zip_source_t zip_source_file_common_new(const char fname, void file, zip_uint64_t start, zip_int64_t len, const zip_stat_t st, zip_source_file_operations_t ops, void ops_userdata, zip_error_t *error) {
52	25	zip_source_file_context_t *ctx;
53	25	zip_source_t *zs;
54	25	zip_source_file_stat_t sb;
55	25	zip_uint64_t length;
56
57	25	if (ops == NULL) {
58	0	zip_error_set(error, ZIP_ER_INVAL, 0);
59	0	return NULL;
60	0	}
61
62	25	if (ops->close == NULL \|\| ops->read == NULL \|\| ops->seek == NULL \|\| ops->stat == NULL) {
63	0	zip_error_set(error, ZIP_ER_INTERNAL, 0);
64	0	return NULL;
65	0	}
66
67	25	if (ops->write != NULL && (ops->commit_write == NULL \|\| ops->create_temp_output == NULL \|\| ops->remove == NULL \|\| ops->rollback_write == NULL \|\| ops->tell == NULL)) {
68	0	zip_error_set(error, ZIP_ER_INTERNAL, 0);
69	0	return NULL;
70	0	}
71
72	25	if (fname != NULL) {
73	25	if (ops->open == NULL \|\| ops->string_duplicate == NULL) {
74	0	zip_error_set(error, ZIP_ER_INTERNAL, 0);
75	0	return NULL;
76	0	}
77	25	}
78	0	else if (file == NULL) {
79	0	zip_error_set(error, ZIP_ER_INVAL, 0);
80	0	return NULL;
81	0	}
82
83	25	if (len < 0) {
84	25	if (len == -1) {
85	25	len = ZIP_LENGTH_TO_END;
86	25	}
87		// TODO: return ZIP_ER_INVAL if len != ZIP_LENGTH_UNCHECKED?
88	25	length = 0;
89	25	}
90	0	else {
91	0	length = (zip_uint64_t)len;
92	0	}
93
94	25	if (start > ZIP_INT64_MAX \|\| start + length < start) {
95	0	zip_error_set(error, ZIP_ER_INVAL, 0);
96	0	return NULL;
97	0	}
98
99	25	if ((ctx = (zip_source_file_context_t *)malloc(sizeof(zip_source_file_context_t))) == NULL) {
100	0	zip_error_set(error, ZIP_ER_MEMORY, 0);
101	0	return NULL;
102	0	}
103
104	25	ctx->ops = ops;
105	25	ctx->ops_userdata = ops_userdata;
106	25	ctx->fname = NULL;
107	25	if (fname) {
108	25	if ((ctx->fname = ops->string_duplicate(ctx, fname)) == NULL) {
109	0	zip_error_set(error, ZIP_ER_MEMORY, 0);
110	0	free(ctx);
111	0	return NULL;
112	0	}
113	25	}
114	25	ctx->f = file;
115	25	ctx->start = start;
116	25	ctx->len = length;
117	25	if (st) {
118	0	(void)memcpy_s(&ctx->st, sizeof(ctx->st), st, sizeof(*st));
119	0	ctx->st.name = NULL;
120	0	ctx->st.valid &= ~ZIP_STAT_NAME;
121	0	}
122	25	else {
123	25	zip_stat_init(&ctx->st);
124	25	}
125
126	25	if (ctx->len > 0) {
127	0	ctx->st.size = ctx->len;
128	0	ctx->st.valid \|= ZIP_STAT_SIZE;
129	0	}
130
131	25	zip_error_init(&ctx->stat_error);
132
133	25	ctx->tmpname = NULL;
134	25	ctx->fout = NULL;
135
136	25	zip_error_init(&ctx->error);
137	25	zip_file_attributes_init(&ctx->attributes);
138
139	25	ctx->supports = ZIP_SOURCE_SUPPORTS_READABLE \| zip_source_make_command_bitmap(ZIP_SOURCE_SUPPORTS, ZIP_SOURCE_TELL, ZIP_SOURCE_SUPPORTS_REOPEN, -1);
140
141	25	zip_source_file_stat_init(&sb);
142	25	if (!ops->stat(ctx, &sb)) {
143	0	_zip_error_copy(error, &ctx->error);
144	0	free(ctx->fname);
145	0	free(ctx);
146	0	return NULL;
147	0	}
148
149	25	if (!sb.exists) {
150	25	if (ctx->fname && ctx->start == 0 && ctx->len == 0 && ops->write != NULL) {
151	25	ctx->supports = ZIP_SOURCE_SUPPORTS_WRITABLE;
152		/* zip_open_from_source checks for this to detect non-existing files */
153	25	zip_error_set(&ctx->stat_error, ZIP_ER_READ, ENOENT);
154	25	}
155	0	else {
156	0	zip_error_set(&ctx->stat_error, ZIP_ER_READ, ENOENT);
157	0	free(ctx->fname);
158	0	free(ctx);
159	0	return NULL;
160	0	}
161	25	}
162	0	else {
163	0	if ((ctx->st.valid & ZIP_STAT_MTIME) == 0) {
164	0	ctx->st.mtime = sb.mtime;
165	0	ctx->st.valid \|= ZIP_STAT_MTIME;
166	0	}
167	0	if (sb.regular_file) {
168	0	ctx->supports = ZIP_SOURCE_SUPPORTS_SEEKABLE;
169
170	0	if (ctx->start + ctx->len > sb.size) {
171	0	zip_error_set(error, ZIP_ER_INVAL, 0);
172	0	free(ctx->fname);
173	0	free(ctx);
174	0	return NULL;
175	0	}
176
177	0	if (ctx->len == 0) {
178	0	if (len != ZIP_LENGTH_UNCHECKED) {
179	0	ctx->len = sb.size - ctx->start;
180	0	ctx->st.size = ctx->len;
181	0	ctx->st.valid \|= ZIP_STAT_SIZE;
182	0	}
183
184		/* when using a partial file, don't allow writing */
185	0	if (ctx->fname && start == 0 && ops->write != NULL) {
186	0	ctx->supports = ZIP_SOURCE_SUPPORTS_WRITABLE;
187	0	}
188	0	}
189	0	}
190
191	0	if (ctx->st.valid & ZIP_STAT_SIZE) {
192	0	ctx->supports \|= ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_AT_EOF);
193	0	}
194
195	0	ctx->supports \|= ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_GET_FILE_ATTRIBUTES);
196	0	}
197
198	25	ctx->supports \|= ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_ACCEPT_EMPTY);
199	25	if (ops->create_temp_output_cloning != NULL) {
200	25	if (ctx->supports & ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_BEGIN_WRITE)) {
201	25	ctx->supports \|= ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_BEGIN_WRITE_CLONING);
202	25	}
203	25	}
204
205	25	if ((zs = zip_source_function_create(read_file, ctx, error)) == NULL) {
206	0	free(ctx->fname);
207	0	free(ctx);
208	0	return NULL;
209	0	}
210
211	25	return zs;
212	25	}
213
214
215	100	static zip_int64_t read_file(void state, void data, zip_uint64_t len, zip_source_cmd_t cmd) {
216	100	zip_source_file_context_t *ctx;
217	100	char *buf;
218
219	100	ctx = (zip_source_file_context_t *)state;
220	100	buf = (char *)data;
221
222	100	switch (cmd) {
223	0	case ZIP_SOURCE_ACCEPT_EMPTY:
224	0	return 0;
225
226	0	case ZIP_SOURCE_AT_EOF:
227		/* We only advertise support for ZIP_SOURCE_AT_EOF if ctx->len is valid. */
228	0	return ctx->offset == ctx->len;
229
230	0	case ZIP_SOURCE_BEGIN_WRITE: {
231	0	zip_int64_t ret;
232		/* write support should not be set if fname is NULL */
233	0	if (ctx->fname == NULL) {
234	0	zip_error_set(&ctx->error, ZIP_ER_INTERNAL, 0);
235	0	return -1;
236	0	}
237	0	ret = ctx->ops->create_temp_output(ctx);
238	0	if (ret == 0) {
239		/* Clear past error. Otherwise the error from zip_source_begin_write_cloning() will persist and be reported on zip_source_close(). */
240	0	zip_error_set(&ctx->error, ZIP_ER_OK, 0);
241	0	}
242	0	return ret;
243	0	}
244
245	0	case ZIP_SOURCE_BEGIN_WRITE_CLONING:
246		/* write support should not be set if fname is NULL */
247	0	if (ctx->fname == NULL) {
248	0	zip_error_set(&ctx->error, ZIP_ER_INTERNAL, 0);
249	0	return -1;
250	0	}
251	0	return ctx->ops->create_temp_output_cloning(ctx, len);
252
253	0	case ZIP_SOURCE_CLOSE:
254	0	if (ctx->fname) {
255	0	ctx->ops->close(ctx);
256	0	ctx->f = NULL;
257	0	}
258	0	return 0;
259
260	0	case ZIP_SOURCE_COMMIT_WRITE: {
261	0	zip_int64_t ret = ctx->ops->commit_write(ctx);
262	0	ctx->fout = NULL;
263	0	if (ret == 0) {
264	0	free(ctx->tmpname);
265	0	ctx->tmpname = NULL;
266	0	}
267	0	return ret;
268	0	}
269
270	25	case ZIP_SOURCE_ERROR:
271	25	return zip_error_to_data(&ctx->error, data, len);
272
273	25	case ZIP_SOURCE_FREE:
274	25	free(ctx->fname);
275	25	free(ctx->tmpname);
276	25	if (ctx->f) {
277	0	ctx->ops->close(ctx);
278	0	}
279	25	free(ctx);
280	25	return 0;
281
282	0	case ZIP_SOURCE_GET_FILE_ATTRIBUTES:
283	0	if (len < sizeof(ctx->attributes)) {
284	0	zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
285	0	return -1;
286	0	}
287	0	(void)memcpy_s(data, sizeof(ctx->attributes), &ctx->attributes, sizeof(ctx->attributes));
288	0	return sizeof(ctx->attributes);
289
290	0	case ZIP_SOURCE_OPEN:
291	0	if (ctx->fname) {
292	0	if (ctx->ops->open(ctx) == false) {
293	0	return -1;
294	0	}
295	0	}
296
297	0	if (ctx->start > 0) { /* TODO: rewind on re-open */
298	0	if (ctx->ops->seek(ctx, ctx->f, (zip_int64_t)ctx->start, SEEK_SET) == false) {
299		/* TODO: skip by reading */
300	0	return -1;
301	0	}
302	0	}
303	0	ctx->offset = 0;
304	0	return 0;
305
306	0	case ZIP_SOURCE_READ: {
307	0	zip_int64_t i;
308	0	zip_uint64_t n;
309
310	0	if (ctx->len > 0) {
311	0	n = ZIP_MIN(ctx->len - ctx->offset, len);
312	0	}
313	0	else {
314	0	n = len;
315	0	}
316
317	0	if ((i = ctx->ops->read(ctx, buf, n)) < 0) {
318	0	zip_error_set(&ctx->error, ZIP_ER_READ, errno);
319	0	return -1;
320	0	}
321	0	ctx->offset += (zip_uint64_t)i;
322
323	0	return i;
324	0	}
325
326	0	case ZIP_SOURCE_REMOVE:
327	0	return ctx->ops->remove(ctx);
328
329	0	case ZIP_SOURCE_ROLLBACK_WRITE:
330	0	ctx->ops->rollback_write(ctx);
331	0	ctx->fout = NULL;
332	0	free(ctx->tmpname);
333	0	ctx->tmpname = NULL;
334	0	return 0;
335
336	0	case ZIP_SOURCE_SEEK: {
337	0	zip_int64_t new_offset = zip_source_seek_compute_offset(ctx->offset, ctx->len, data, len, &ctx->error);
338
339	0	if (new_offset < 0) {
340	0	return -1;
341	0	}
342
343		/* The actual offset inside the file must be representable as zip_int64_t. */
344	0	if (new_offset > ZIP_INT64_MAX - (zip_int64_t)ctx->start) {
345	0	zip_error_set(&ctx->error, ZIP_ER_SEEK, EOVERFLOW);
346	0	return -1;
347	0	}
348
349	0	ctx->offset = (zip_uint64_t)new_offset;
350
351	0	if (ctx->ops->seek(ctx, ctx->f, (zip_int64_t)(ctx->offset + ctx->start), SEEK_SET) == false) {
352	0	return -1;
353	0	}
354	0	return 0;
355	0	}
356
357	0	case ZIP_SOURCE_SEEK_WRITE: {
358	0	zip_source_args_seek_t *args;
359
360	0	args = ZIP_SOURCE_GET_ARGS(zip_source_args_seek_t, data, len, &ctx->error);
361	0	if (args == NULL) {
362	0	return -1;
363	0	}
364
365	0	if (ctx->ops->seek(ctx, ctx->fout, args->offset, args->whence) == false) {
366	0	return -1;
367	0	}
368	0	return 0;
369	0	}
370
371	25	case ZIP_SOURCE_STAT: {
372	25	if (len < sizeof(ctx->st)) {
373	0	return -1;
374	0	}
375
376	25	if (zip_error_code_zip(&ctx->stat_error) != 0) {
377	25	zip_error_set(&ctx->error, zip_error_code_zip(&ctx->stat_error), zip_error_code_system(&ctx->stat_error));
378	25	return -1;
379	25	}
380
381	0	(void)memcpy_s(data, sizeof(ctx->st), &ctx->st, sizeof(ctx->st));
382	0	return sizeof(ctx->st);
383	25	}
384
385	25	case ZIP_SOURCE_SUPPORTS:
386	25	return ctx->supports;
387
388	0	case ZIP_SOURCE_TELL:
389	0	return (zip_int64_t)ctx->offset;
390
391	0	case ZIP_SOURCE_TELL_WRITE:
392	0	return ctx->ops->tell(ctx, ctx->fout);
393
394	0	case ZIP_SOURCE_WRITE:
395	0	return ctx->ops->write(ctx, data, len);
396
397	0	default:
398	0	zip_error_set(&ctx->error, ZIP_ER_OPNOTSUPP, 0);
399	0	return -1;
400	100	}
401	100	}