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;
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 				break; /* EOF */
87 			}
88 			z->next_in = zb->inbuf;
89 			z->avail_in = n;
90 		}
91 		ret = inflate(z, Z_SYNC_FLUSH);
92 	} while (ret == Z_OK && z->avail_out > 0);
93 
94 	if (ret == Z_OK) {
95 		zb->flags |= GOT_ZSTREAM_F_HAVE_MORE;
96 	} else {
97 		if (ret != Z_STREAM_END)
98 			return got_error(GOT_ERR_DECOMPRESSION);
99 		zb->flags &= ~GOT_ZSTREAM_F_HAVE_MORE;
100 	}
101 
102 	*outlenp = z->total_out - last_total_out;
103 	return NULL;
104 }
105 
106 void
107 got_inflate_end(struct got_zstream_buf *zb)
108 {
109 	free(zb->inbuf);
110 	if (zb->flags & GOT_ZSTREAM_F_OWN_OUTBUF)
111 		free(zb->outbuf);
112 	inflateEnd(&zb->z);
113 }
114 
115 const struct got_error *
116 got_inflate_to_mem(uint8_t **outbuf, size_t *outlen, FILE *f)
117 {
118 	const struct got_error *err;
119 	size_t avail;
120 	struct got_zstream_buf zb;
121 	void *newbuf;
122 
123 	*outbuf = calloc(1, GOT_ZSTREAM_BUFSIZE);
124 	if (*outbuf == NULL)
125 		return got_error_from_errno();
126 	err = got_inflate_init(&zb, *outbuf, GOT_ZSTREAM_BUFSIZE);
127 	if (err)
128 		return err;
129 
130 	*outlen = 0;
131 
132 	do {
133 		err = got_inflate_read(&zb, f, &avail);
134 		if (err)
135 			return err;
136 		*outlen += avail;
137 		if (zb.flags & GOT_ZSTREAM_F_HAVE_MORE) {
138 			newbuf = reallocarray(*outbuf, 1,
139 			    *outlen + GOT_ZSTREAM_BUFSIZE);
140 			if (newbuf == NULL) {
141 				err = got_error_from_errno();
142 				free(*outbuf);
143 				*outbuf = NULL;
144 				*outlen = 0;
145 				goto done;
146 			}
147 			*outbuf = newbuf;
148 			zb.outbuf = newbuf + *outlen;
149 			zb.outlen = GOT_ZSTREAM_BUFSIZE;
150 		}
151 	} while (zb.flags & GOT_ZSTREAM_F_HAVE_MORE);
152 
153 done:
154 	got_inflate_end(&zb);
155 	return err;
156 }
157 
158 const struct got_error *
159 got_inflate_to_file(size_t *outlen, FILE *infile, FILE *outfile)
160 {
161 	const struct got_error *err;
162 	size_t avail;
163 	struct got_zstream_buf zb;
164 
165 	err = got_inflate_init(&zb, NULL, GOT_ZSTREAM_BUFSIZE);
166 	if (err)
167 		goto done;
168 
169 	*outlen = 0;
170 
171 	do {
172 		err = got_inflate_read(&zb, infile, &avail);
173 		if (err)
174 			return err;
175 		if (avail > 0) {
176 			size_t n;
177 			n = fwrite(zb.outbuf, avail, 1, outfile);
178 			if (n != 1) {
179 				err = got_ferror(outfile, GOT_ERR_IO);
180 				goto done;
181 			}
182 			*outlen += avail;
183 		}
184 	} while (zb.flags & GOT_ZSTREAM_F_HAVE_MORE);
185 
186 done:
187 	if (err == NULL)
188 		rewind(outfile);
189 	got_inflate_end(&zb);
190 	return err;
191 }