1/*
2 * libwebsockets - small server side websockets and web server implementation
3 *
4 * Copyright (C) 2010 - 2019 Andy Green <andy@warmcat.com>
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22 * IN THE SOFTWARE.
23 */
24
25#if !defined(_GNU_SOURCE)
26#define _GNU_SOURCE
27#endif
28#include "private-lib-core.h"
29
30#include <pwd.h>
31#include <grp.h>
32
33#ifdef LWS_WITH_PLUGINS
34#include <dlfcn.h>
35#endif
36#include <dirent.h>
37
38int lws_plat_apply_FD_CLOEXEC(int n)
39{
40	if (n == -1)
41		return 0;
42
43	return fcntl(n, F_SETFD, FD_CLOEXEC);
44}
45
46int
47lws_plat_write_file(const char *filename, void *buf, size_t len)
48{
49	ssize_t m;
50	int fd;
51
52	fd = lws_open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600);
53
54	if (fd == -1)
55		return 1;
56
57	m = write(fd, buf, len);
58	close(fd);
59
60	if (m < 0)
61		return 1;
62
63	return (size_t)m != len;
64}
65
66int
67lws_plat_read_file(const char *filename, void *buf, size_t len)
68{
69	int fd = lws_open(filename, O_RDONLY);
70	ssize_t n;
71
72	if (fd == -1)
73		return -1;
74
75	n = read(fd, buf, len);
76	close(fd);
77
78	return (int)n;
79}
80
81lws_fop_fd_t
82_lws_plat_file_open(const struct lws_plat_file_ops *fops, const char *filename,
83		    const char *vpath, lws_fop_flags_t *flags)
84{
85	struct stat stat_buf;
86	int ret = lws_open(filename, (*flags) & LWS_FOP_FLAGS_MASK, 0664);
87	lws_fop_fd_t fop_fd;
88
89	if (ret < 0)
90		return NULL;
91
92	if (fstat(ret, &stat_buf) < 0)
93		goto bail;
94
95	fop_fd = malloc(sizeof(*fop_fd));
96	if (!fop_fd)
97		goto bail;
98
99	fop_fd->fops = fops;
100	fop_fd->flags = *flags;
101	fop_fd->fd = ret;
102	fop_fd->filesystem_priv = NULL; /* we don't use it */
103	fop_fd->len = (lws_filepos_t)stat_buf.st_size;
104	fop_fd->pos = 0;
105
106	return fop_fd;
107
108bail:
109	close(ret);
110	return NULL;
111}
112
113int
114_lws_plat_file_close(lws_fop_fd_t *fop_fd)
115{
116	int fd = (*fop_fd)->fd;
117
118	free(*fop_fd);
119	*fop_fd = NULL;
120
121	return close(fd);
122}
123
124lws_fileofs_t
125_lws_plat_file_seek_cur(lws_fop_fd_t fop_fd, lws_fileofs_t offset)
126{
127	lws_fileofs_t r;
128
129	if (offset > 0 &&
130	    offset > (lws_fileofs_t)fop_fd->len - (lws_fileofs_t)fop_fd->pos)
131		offset = (lws_fileofs_t)(fop_fd->len - fop_fd->pos);
132
133	if ((lws_fileofs_t)fop_fd->pos + offset < 0)
134		offset = (lws_fileofs_t)(-fop_fd->pos);
135
136	r = lseek(fop_fd->fd, (off_t)offset, SEEK_CUR);
137
138	if (r >= 0)
139		fop_fd->pos = (lws_filepos_t)r;
140	else
141		lwsl_err("error seeking from cur %ld, offset %ld\n",
142                        (long)fop_fd->pos, (long)offset);
143
144	return r;
145}
146
147int
148_lws_plat_file_read(lws_fop_fd_t fop_fd, lws_filepos_t *amount,
149		    uint8_t *buf, lws_filepos_t len)
150{
151	ssize_t n;
152
153	n = read((int)fop_fd->fd, buf, (size_t)len);
154	if (n == -1l) {
155		*amount = 0;
156		return -1;
157	}
158	fop_fd->pos = (lws_filepos_t)(fop_fd->pos + (lws_filepos_t)n);
159	lwsl_debug("%s: read %ld of req %ld, pos %ld, len %ld\n", __func__,
160			(long)n, (long)len, (long)fop_fd->pos,
161			(long)fop_fd->len);
162	*amount = (lws_filepos_t)n;
163
164	return 0;
165}
166
167int
168_lws_plat_file_write(lws_fop_fd_t fop_fd, lws_filepos_t *amount,
169		     uint8_t *buf, lws_filepos_t len)
170{
171	ssize_t n;
172
173	n = write((int)fop_fd->fd, buf, (size_t)len);
174	if (n == -1) {
175		*amount = 0;
176		return -1;
177	}
178
179	fop_fd->pos = (lws_filepos_t)(fop_fd->pos + (lws_filepos_t)n);
180	*amount = (lws_filepos_t)n;
181
182	return 0;
183}
184
185