xref: /freebsd/contrib/bc/src/read.c (revision 0a36787e4c1fa0cf77dcf83be0867178476e372b)
1 /*
2  * *****************************************************************************
3  *
4  * SPDX-License-Identifier: BSD-2-Clause
5  *
6  * Copyright (c) 2018-2021 Gavin D. Howard and contributors.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions are met:
10  *
11  * * Redistributions of source code must retain the above copyright notice, this
12  *   list of conditions and the following disclaimer.
13  *
14  * * Redistributions in binary form must reproduce the above copyright notice,
15  *   this list of conditions and the following disclaimer in the documentation
16  *   and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  *
30  * *****************************************************************************
31  *
32  * Code to handle special I/O for bc.
33  *
34  */
35 
36 #include <assert.h>
37 #include <ctype.h>
38 #include <errno.h>
39 #include <stdlib.h>
40 #include <string.h>
41 
42 #include <signal.h>
43 
44 #include <fcntl.h>
45 #include <sys/stat.h>
46 
47 #ifndef _WIN32
48 #include <unistd.h>
49 #endif // _WIN32
50 
51 #include <read.h>
52 #include <history.h>
53 #include <program.h>
54 #include <vm.h>
55 
56 static int bc_read_open(const char* path, int mode) {
57 
58 	int fd;
59 
60 #ifndef _WIN32
61 	fd = open(path, mode);
62 #else // _WIN32
63 	fd = -1;
64 	open(&fd, path, mode);
65 #endif
66 
67 	return fd;
68 }
69 
70 static bool bc_read_binary(const char *buf, size_t size) {
71 
72 	size_t i;
73 
74 	for (i = 0; i < size; ++i) {
75 		if (BC_ERR(BC_READ_BIN_CHAR(buf[i]))) return true;
76 	}
77 
78 	return false;
79 }
80 
81 bool bc_read_buf(BcVec *vec, char *buf, size_t *buf_len) {
82 
83 	char *nl;
84 
85 	if (!*buf_len) return false;
86 
87 	nl = strchr(buf, '\n');
88 
89 	if (nl != NULL) {
90 
91 		size_t nllen = (size_t) ((nl + 1) - buf);
92 
93 		nllen = *buf_len >= nllen ? nllen : *buf_len;
94 
95 		bc_vec_npush(vec, nllen, buf);
96 		*buf_len -= nllen;
97 		memmove(buf, nl + 1, *buf_len + 1);
98 
99 		return true;
100 	}
101 
102 	bc_vec_npush(vec, *buf_len, buf);
103 	*buf_len = 0;
104 
105 	return false;
106 }
107 
108 BcStatus bc_read_chars(BcVec *vec, const char *prompt) {
109 
110 	bool done = false;
111 
112 	assert(vec != NULL && vec->size == sizeof(char));
113 
114 	BC_SIG_ASSERT_NOT_LOCKED;
115 
116 	bc_vec_popAll(vec);
117 
118 #if BC_ENABLE_PROMPT
119 	if (BC_USE_PROMPT) {
120 		bc_file_puts(&vm.fout, bc_flush_none, prompt);
121 		bc_file_flush(&vm.fout, bc_flush_none);
122 	}
123 #endif // BC_ENABLE_PROMPT
124 
125 	if (bc_read_buf(vec, vm.buf, &vm.buf_len)) {
126 		bc_vec_pushByte(vec, '\0');
127 		return BC_STATUS_SUCCESS;
128 	}
129 
130 	while (!done) {
131 
132 		ssize_t r;
133 
134 		BC_SIG_LOCK;
135 
136 		r = read(STDIN_FILENO, vm.buf + vm.buf_len,
137 		         BC_VM_STDIN_BUF_SIZE - vm.buf_len);
138 
139 		if (BC_UNLIKELY(r < 0)) {
140 
141 			if (errno == EINTR) {
142 
143 				if (vm.status == (sig_atomic_t) BC_STATUS_QUIT) {
144 					BC_SIG_UNLOCK;
145 					return BC_STATUS_QUIT;
146 				}
147 
148 				assert(vm.sig);
149 
150 				vm.status = (sig_atomic_t) BC_STATUS_SUCCESS;
151 #if BC_ENABLE_PROMPT
152 				if (BC_USE_PROMPT)
153 					bc_file_puts(&vm.fout, bc_flush_none, prompt);
154 #endif // BC_ENABLE_PROMPT
155 				bc_file_flush(&vm.fout, bc_flush_none);
156 
157 				BC_SIG_UNLOCK;
158 
159 				continue;
160 			}
161 
162 			BC_SIG_UNLOCK;
163 
164 			bc_vm_fatalError(BC_ERR_FATAL_IO_ERR);
165 		}
166 
167 		BC_SIG_UNLOCK;
168 
169 		if (r == 0) {
170 			bc_vec_pushByte(vec, '\0');
171 			return BC_STATUS_EOF;
172 		}
173 
174 		vm.buf_len += (size_t) r;
175 		vm.buf[vm.buf_len] = '\0';
176 
177 		done = bc_read_buf(vec, vm.buf, &vm.buf_len);
178 	}
179 
180 	bc_vec_pushByte(vec, '\0');
181 
182 	return BC_STATUS_SUCCESS;
183 }
184 
185 BcStatus bc_read_line(BcVec *vec, const char *prompt) {
186 
187 	BcStatus s;
188 
189 #if BC_ENABLE_HISTORY
190 	if (BC_TTY && !vm.history.badTerm)
191 		s = bc_history_line(&vm.history, vec, prompt);
192 	else s = bc_read_chars(vec, prompt);
193 #else // BC_ENABLE_HISTORY
194 	s = bc_read_chars(vec, prompt);
195 #endif // BC_ENABLE_HISTORY
196 
197 	if (BC_ERR(bc_read_binary(vec->v, vec->len - 1)))
198 		bc_vm_verr(BC_ERR_FATAL_BIN_FILE, bc_program_stdin_name);
199 
200 	return s;
201 }
202 
203 void bc_read_file(const char *path, char **buf) {
204 
205 	BcErr e = BC_ERR_FATAL_IO_ERR;
206 	size_t size, r;
207 	struct stat pstat;
208 	int fd;
209 
210 	BC_SIG_ASSERT_LOCKED;
211 
212 	assert(path != NULL);
213 
214 	fd = bc_read_open(path, O_RDONLY);
215 
216 	if (BC_ERR(fd < 0)) bc_vm_verr(BC_ERR_FATAL_FILE_ERR, path);
217 	if (BC_ERR(fstat(fd, &pstat) == -1)) goto malloc_err;
218 
219 	if (BC_ERR(S_ISDIR(pstat.st_mode))) {
220 		e = BC_ERR_FATAL_PATH_DIR;
221 		goto malloc_err;
222 	}
223 
224 	size = (size_t) pstat.st_size;
225 	*buf = bc_vm_malloc(size + 1);
226 
227 	r = (size_t) read(fd, *buf, size);
228 	if (BC_ERR(r != size)) goto read_err;
229 
230 	(*buf)[size] = '\0';
231 
232 	if (BC_ERR(bc_read_binary(*buf, size))) {
233 		e = BC_ERR_FATAL_BIN_FILE;
234 		goto read_err;
235 	}
236 
237 	close(fd);
238 
239 	return;
240 
241 read_err:
242 	free(*buf);
243 malloc_err:
244 	close(fd);
245 	bc_vm_verr(e, path);
246 }
247