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_path_priv.h"
29 #include "got_zb_priv.h"
30 
31 const struct got_error *
32 got_inflate_init(struct got_zstream_buf *zb, 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(GOT_ERR_NO_MEM);
50 		goto done;
51 	}
52 
53 	zb->outbuf = calloc(1, zb->outlen);
54 	if (zb->outbuf == NULL) {
55 		err = got_error(GOT_ERR_NO_MEM);
56 		goto done;
57 	}
58 
59 done:
60 	if (err)
61 		got_inflate_end(zb);
62 	return err;
63 }
64 
65 const struct got_error *
66 got_inflate_read(struct got_zstream_buf *zb, FILE *f, size_t *outlenp)
67 {
68 	size_t last_total_out = zb->z.total_out;
69 	z_stream *z = &zb->z;
70 	int ret;
71 
72 	z->next_out = zb->outbuf;
73 	z->avail_out = zb->outlen;
74 
75 	*outlenp = 0;
76 	do {
77 		if (z->avail_in == 0) {
78 			size_t n = fread(zb->inbuf, 1, zb->inlen, f);
79 			if (n == 0) {
80 				if (ferror(f))
81 					return got_ferror(f, GOT_ERR_IO);
82 				break; /* EOF */
83 			}
84 			z->next_in = zb->inbuf;
85 			z->avail_in = n;
86 		}
87 		ret = inflate(z, Z_SYNC_FLUSH);
88 	} while (ret == Z_OK && z->avail_out > 0);
89 
90 	if (ret == Z_OK) {
91 		zb->flags |= GOT_ZSTREAM_F_HAVE_MORE;
92 	} else {
93 		if (ret != Z_STREAM_END)
94 			return got_error(GOT_ERR_DECOMPRESSION);
95 		zb->flags &= ~GOT_ZSTREAM_F_HAVE_MORE;
96 	}
97 
98 	*outlenp = z->total_out - last_total_out;
99 	return NULL;
100 }
101 
102 void
103 got_inflate_end(struct got_zstream_buf *zb)
104 {
105 	free(zb->inbuf);
106 	free(zb->outbuf);
107 	inflateEnd(&zb->z);
108 }
109 
110 const struct got_error *
111 got_inflate_to_mem(uint8_t **outbuf, size_t *outlen, FILE *f)
112 {
113 	const struct got_error *err;
114 	size_t avail;
115 	struct got_zstream_buf zb;
116 	void *newbuf;
117 
118 	err = got_inflate_init(&zb, 8192);
119 	if (err)
120 		return err;
121 
122 	*outbuf = NULL;
123 	*outlen = 0;
124 
125 	do {
126 		err = got_inflate_read(&zb, f, &avail);
127 		if (err)
128 			return err;
129 		if (avail > 0) {
130 			newbuf = reallocarray(*outbuf, 1, *outlen + avail);
131 			if (newbuf == NULL) {
132 				free(*outbuf);
133 				*outbuf = NULL;
134 				*outlen = 0;
135 				err = got_error(GOT_ERR_NO_MEM);
136 				goto done;
137 			}
138 			memcpy(newbuf + *outlen, zb.outbuf, avail);
139 			*outbuf = newbuf;
140 			*outlen += avail;
141 		}
142 	} while (zb.flags & GOT_ZSTREAM_F_HAVE_MORE);
143 
144 done:
145 	got_inflate_end(&zb);
146 	return err;
147 }
148 
149 const struct got_error *
150 got_inflate_to_file(size_t *outlen, FILE *infile, FILE *outfile)
151 {
152 	const struct got_error *err;
153 	size_t avail;
154 	struct got_zstream_buf zb;
155 	void *newbuf;
156 
157 	err = got_inflate_init(&zb, 8192);
158 	if (err)
159 		goto done;
160 
161 	*outlen = 0;
162 
163 	do {
164 		err = got_inflate_read(&zb, infile, &avail);
165 		if (err)
166 			return err;
167 		if (avail > 0) {
168 			size_t n;
169 			n = fwrite(zb.outbuf, avail, 1, outfile);
170 			if (n != 1) {
171 				err = got_ferror(outfile, GOT_ERR_IO);
172 				goto done;
173 			}
174 			*outlen += avail;
175 		}
176 	} while (zb.flags & GOT_ZSTREAM_F_HAVE_MORE);
177 
178 done:
179 	if (err == NULL)
180 		rewind(outfile);
181 	got_inflate_end(&zb);
182 	return err;
183 }