1 /*
2  * Copyright (c) 2018 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/queue.h>
18 
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <string.h>
22 #include <sha1.h>
23 #include <zlib.h>
24 
25 #include "got_error.h"
26 #include "got_object.h"
27 
28 #include "got_lib_path.h"
29 #include "got_lib_zbuf.h"
30 
31 const struct got_error *
32 got_inflate_init(struct got_zstream_buf *zb, uint8_t *outbuf, size_t bufsize)
33 {
34 	const struct got_error *err = NULL;
35 
36 	memset(zb, 0, sizeof(*zb));
37 
38 	zb->z.zalloc = Z_NULL;
39 	zb->z.zfree = Z_NULL;
40 	if (inflateInit(&zb->z) != Z_OK) {
41 		err = got_error(GOT_ERR_IO);
42 		goto done;
43 	}
44 
45 	zb->inlen = zb->outlen = bufsize;
46 
47 	zb->inbuf = calloc(1, zb->inlen);
48 	if (zb->inbuf == NULL) {
49 		err = got_error_from_errno();
50 		goto done;
51 	}
52 
53 	if (outbuf == NULL) {
54 		zb->outbuf = calloc(1, zb->outlen);
55 		if (zb->outbuf == NULL) {
56 			err = got_error_from_errno();
57 			goto done;
58 		}
59 		zb->flags |= GOT_ZSTREAM_F_OWN_OUTBUF;
60 	} else
61 		zb->outbuf = outbuf;
62 
63 done:
64 	if (err)
65 		got_inflate_end(zb);
66 	return err;
67 }
68 
69 const struct got_error *
70 got_inflate_read(struct got_zstream_buf *zb, FILE *f, size_t *outlenp)
71 {
72 	size_t last_total_out = zb->z.total_out;
73 	z_stream *z = &zb->z;
74 	int ret = Z_ERRNO;
75 
76 	z->next_out = zb->outbuf;
77 	z->avail_out = zb->outlen;
78 
79 	*outlenp = 0;
80 	do {
81 		if (z->avail_in == 0) {
82 			size_t n = fread(zb->inbuf, 1, zb->inlen, f);
83 			if (n == 0) {
84 				if (ferror(f))
85 					return got_ferror(f, GOT_ERR_IO);
86 				/* EOF */
87 				ret = Z_STREAM_END;
88 				break;
89 			}
90 			z->next_in = zb->inbuf;
91 			z->avail_in = n;
92 		}
93 		ret = inflate(z, Z_SYNC_FLUSH);
94 	} while (ret == Z_OK && z->avail_out > 0);
95 
96 	if (ret == Z_OK) {
97 		zb->flags |= GOT_ZSTREAM_F_HAVE_MORE;
98 	} else {
99 		if (ret != Z_STREAM_END)
100 			return got_error(GOT_ERR_DECOMPRESSION);
101 		zb->flags &= ~GOT_ZSTREAM_F_HAVE_MORE;
102 	}
103 
104 	*outlenp = z->total_out - last_total_out;
105 	return NULL;
106 }
107 
108 void
109 got_inflate_end(struct got_zstream_buf *zb)
110 {
111 	free(zb->inbuf);
112 	if (zb->flags & GOT_ZSTREAM_F_OWN_OUTBUF)
113 		free(zb->outbuf);
114 	inflateEnd(&zb->z);
115 }
116 
117 const struct got_error *
118 got_inflate_to_mem(uint8_t **outbuf, size_t *outlen, FILE *f)
119 {
120 	const struct got_error *err;
121 	size_t avail;
122 	struct got_zstream_buf zb;
123 	void *newbuf;
124 
125 	*outbuf = calloc(1, GOT_ZSTREAM_BUFSIZE);
126 	if (*outbuf == NULL)
127 		return got_error_from_errno();
128 	err = got_inflate_init(&zb, *outbuf, GOT_ZSTREAM_BUFSIZE);
129 	if (err)
130 		return err;
131 
132 	*outlen = 0;
133 
134 	do {
135 		err = got_inflate_read(&zb, f, &avail);
136 		if (err)
137 			return err;
138 		*outlen += avail;
139 		if (zb.flags & GOT_ZSTREAM_F_HAVE_MORE) {
140 			newbuf = reallocarray(*outbuf, 1,
141 			    *outlen + GOT_ZSTREAM_BUFSIZE);
142 			if (newbuf == NULL) {
143 				err = got_error_from_errno();
144 				free(*outbuf);
145 				*outbuf = NULL;
146 				*outlen = 0;
147 				goto done;
148 			}
149 			*outbuf = newbuf;
150 			zb.outbuf = newbuf + *outlen;
151 			zb.outlen = GOT_ZSTREAM_BUFSIZE;
152 		}
153 	} while (zb.flags & GOT_ZSTREAM_F_HAVE_MORE);
154 
155 done:
156 	got_inflate_end(&zb);
157 	return err;
158 }
159 
160 const struct got_error *
161 got_inflate_to_file(size_t *outlen, FILE *infile, FILE *outfile)
162 {
163 	const struct got_error *err;
164 	size_t avail;
165 	struct got_zstream_buf zb;
166 
167 	err = got_inflate_init(&zb, NULL, GOT_ZSTREAM_BUFSIZE);
168 	if (err)
169 		goto done;
170 
171 	*outlen = 0;
172 
173 	do {
174 		err = got_inflate_read(&zb, infile, &avail);
175 		if (err)
176 			return err;
177 		if (avail > 0) {
178 			size_t n;
179 			n = fwrite(zb.outbuf, avail, 1, outfile);
180 			if (n != 1) {
181 				err = got_ferror(outfile, GOT_ERR_IO);
182 				goto done;
183 			}
184 			*outlen += avail;
185 		}
186 	} while (zb.flags & GOT_ZSTREAM_F_HAVE_MORE);
187 
188 done:
189 	if (err == NULL)
190 		rewind(outfile);
191 	got_inflate_end(&zb);
192 	return err;
193 }