xref: /freebsd/contrib/bc/src/read.c (revision fa9012aef1ad596a99950f986cf1fb31111c034a)
1 /*
2  * *****************************************************************************
3  *
4  * Copyright (c) 2018-2020 Gavin D. Howard and contributors.
5  *
6  * All rights reserved.
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 #include <unistd.h>
47 
48 #include <read.h>
49 #include <history.h>
50 #include <program.h>
51 #include <vm.h>
52 
53 static bool bc_read_binary(const char *buf, size_t size) {
54 
55 	size_t i;
56 
57 	for (i = 0; i < size; ++i) {
58 		if (BC_ERR(BC_READ_BIN_CHAR(buf[i]))) return true;
59 	}
60 
61 	return false;
62 }
63 
64 static bool bc_read_buf(BcVec *vec) {
65 
66 	char *nl;
67 
68 	if (!vm.buf_len) return false;
69 
70 	nl = strchr(vm.buf, '\n');
71 
72 	if (nl != NULL) {
73 
74 		size_t nllen = (size_t) ((nl + 1) - vm.buf);
75 
76 		nllen = vm.buf_len >= nllen ? nllen : vm.buf_len;
77 
78 		bc_vec_npush(vec, nllen, vm.buf);
79 		vm.buf_len -= nllen;
80 		memmove(vm.buf, nl + 1, vm.buf_len);
81 
82 		return true;
83 	}
84 
85 	bc_vec_npush(vec, vm.buf_len, vm.buf);
86 	vm.buf_len = 0;
87 
88 	return false;
89 }
90 
91 BcStatus bc_read_chars(BcVec *vec, const char *prompt) {
92 
93 	bool done = false;
94 
95 	assert(vec != NULL && vec->size == sizeof(char));
96 
97 	BC_SIG_ASSERT_NOT_LOCKED;
98 
99 	bc_vec_npop(vec, vec->len);
100 
101 #if BC_ENABLE_PROMPT
102 	if (BC_USE_PROMPT) {
103 		bc_file_puts(&vm.fout, prompt);
104 		bc_file_flush(&vm.fout);
105 	}
106 #endif // BC_ENABLE_PROMPT
107 
108 	if (bc_read_buf(vec)) {
109 		bc_vec_pushByte(vec, '\0');
110 		return BC_STATUS_SUCCESS;
111 	}
112 
113 	while (!done) {
114 
115 		ssize_t r;
116 
117 		BC_SIG_LOCK;
118 
119 		r = read(STDIN_FILENO, vm.buf + vm.buf_len,
120 		         BC_VM_STDIN_BUF_SIZE - vm.buf_len);
121 
122 		if (BC_UNLIKELY(r < 0)) {
123 
124 			if (errno == EINTR) {
125 
126 				if (vm.status == (sig_atomic_t) BC_STATUS_QUIT) {
127 					BC_SIG_UNLOCK;
128 					return BC_STATUS_QUIT;
129 				}
130 
131 				assert(vm.sig);
132 
133 				vm.status = (sig_atomic_t) BC_STATUS_SUCCESS;
134 #if BC_ENABLE_PROMPT
135 				if (BC_USE_PROMPT) bc_file_puts(&vm.fout, prompt);
136 #endif // BC_ENABLE_PROMPT
137 				bc_file_flush(&vm.fout);
138 
139 				BC_SIG_UNLOCK;
140 
141 				continue;
142 			}
143 
144 			BC_SIG_UNLOCK;
145 
146 			bc_vm_err(BC_ERROR_FATAL_IO_ERR);
147 		}
148 
149 		BC_SIG_UNLOCK;
150 
151 		if (r == 0) {
152 			bc_vec_pushByte(vec, '\0');
153 			return BC_STATUS_EOF;
154 		}
155 
156 		vm.buf_len += (size_t) r;
157 
158 		done = bc_read_buf(vec);
159 	}
160 
161 	bc_vec_pushByte(vec, '\0');
162 
163 	return BC_STATUS_SUCCESS;
164 }
165 
166 BcStatus bc_read_line(BcVec *vec, const char *prompt) {
167 
168 	BcStatus s;
169 
170 #if BC_ENABLE_HISTORY
171 	if (BC_TTY && !vm.history.badTerm)
172 		s = bc_history_line(&vm.history, vec, prompt);
173 	else s = bc_read_chars(vec, prompt);
174 #else // BC_ENABLE_HISTORY
175 	s = bc_read_chars(vec, prompt);
176 #endif // BC_ENABLE_HISTORY
177 
178 	if (BC_ERR(bc_read_binary(vec->v, vec->len - 1)))
179 		bc_vm_verr(BC_ERROR_FATAL_BIN_FILE, bc_program_stdin_name);
180 
181 	return s;
182 }
183 
184 void bc_read_file(const char *path, char **buf) {
185 
186 	BcError e = BC_ERROR_FATAL_IO_ERR;
187 	size_t size, r;
188 	struct stat pstat;
189 	int fd;
190 
191 	BC_SIG_ASSERT_LOCKED;
192 
193 	assert(path != NULL);
194 
195 	fd = open(path, O_RDONLY);
196 	if (BC_ERR(fd < 0)) bc_vm_verr(BC_ERROR_FATAL_FILE_ERR, path);
197 	if (BC_ERR(fstat(fd, &pstat) == -1)) goto malloc_err;
198 
199 	if (BC_ERR(S_ISDIR(pstat.st_mode))) {
200 		e = BC_ERROR_FATAL_PATH_DIR;
201 		goto malloc_err;
202 	}
203 
204 	size = (size_t) pstat.st_size;
205 	*buf = bc_vm_malloc(size + 1);
206 
207 	r = (size_t) read(fd, *buf, size);
208 	if (BC_ERR(r != size)) goto read_err;
209 
210 	(*buf)[size] = '\0';
211 
212 	if (BC_ERR(bc_read_binary(*buf, size))) {
213 		e = BC_ERROR_FATAL_BIN_FILE;
214 		goto read_err;
215 	}
216 
217 	close(fd);
218 
219 	return;
220 
221 read_err:
222 	free(*buf);
223 malloc_err:
224 	close(fd);
225 	bc_vm_verr(e, path);
226 }
227