No idea
ATParser.cpp@9:9bcb87c27208, 2015-07-20 (annotated)
- Committer:
- geky
- Date:
- Mon Jul 20 21:28:39 2015 +0000
- Revision:
- 9:9bcb87c27208
- Parent:
- 8:91515b168c70
- Child:
- 10:553f9ffaf657
Added direct printf/scanf methods as alternatives to the newline-based send/recv methods.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
geky | 0:c741e144517c | 1 | /* Copyright (c) 2015 ARM Limited |
geky | 0:c741e144517c | 2 | * |
geky | 0:c741e144517c | 3 | * Licensed under the Apache License, Version 2.0 (the "License"); |
geky | 0:c741e144517c | 4 | * you may not use this file except in compliance with the License. |
geky | 0:c741e144517c | 5 | * You may obtain a copy of the License at |
geky | 0:c741e144517c | 6 | * |
geky | 0:c741e144517c | 7 | * http://www.apache.org/licenses/LICENSE-2.0 |
geky | 0:c741e144517c | 8 | * |
geky | 0:c741e144517c | 9 | * Unless required by applicable law or agreed to in writing, software |
geky | 0:c741e144517c | 10 | * distributed under the License is distributed on an "AS IS" BASIS, |
geky | 0:c741e144517c | 11 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
geky | 0:c741e144517c | 12 | * See the License for the specific language governing permissions and |
geky | 0:c741e144517c | 13 | * limitations under the License. |
geky | 0:c741e144517c | 14 | * |
geky | 0:c741e144517c | 15 | * @section DESCRIPTION |
geky | 0:c741e144517c | 16 | * |
geky | 0:c741e144517c | 17 | * Parser for the AT command syntax |
geky | 0:c741e144517c | 18 | * |
geky | 0:c741e144517c | 19 | */ |
geky | 0:c741e144517c | 20 | |
geky | 0:c741e144517c | 21 | #include "ATParser.h" |
geky | 0:c741e144517c | 22 | |
geky | 0:c741e144517c | 23 | // This can be defined to assist in debugging |
geky | 2:4d68f546861c | 24 | #define AT_ECHO 1 |
geky | 0:c741e144517c | 25 | |
geky | 0:c741e144517c | 26 | |
geky | 0:c741e144517c | 27 | // getc/putc handling with timeouts |
geky | 4:38acbd6f9d9e | 28 | int ATParser::putc(char c) { |
geky | 0:c741e144517c | 29 | Timer timer; |
geky | 0:c741e144517c | 30 | timer.start(); |
geky | 0:c741e144517c | 31 | |
geky | 0:c741e144517c | 32 | while (true) { |
geky | 0:c741e144517c | 33 | if (_serial->writeable()) |
geky | 0:c741e144517c | 34 | return _serial->putc(c); |
geky | 0:c741e144517c | 35 | |
geky | 0:c741e144517c | 36 | if (timer.read_ms() > _timeout) |
geky | 0:c741e144517c | 37 | return -1; |
geky | 0:c741e144517c | 38 | } |
geky | 0:c741e144517c | 39 | } |
geky | 0:c741e144517c | 40 | |
geky | 4:38acbd6f9d9e | 41 | int ATParser::getc() { |
geky | 0:c741e144517c | 42 | Timer timer; |
geky | 0:c741e144517c | 43 | timer.start(); |
geky | 0:c741e144517c | 44 | |
geky | 0:c741e144517c | 45 | while (true) { |
geky | 0:c741e144517c | 46 | if (_serial->readable()) |
geky | 0:c741e144517c | 47 | return _serial->getc(); |
geky | 0:c741e144517c | 48 | |
geky | 0:c741e144517c | 49 | if (timer.read_ms() > _timeout) |
geky | 0:c741e144517c | 50 | return -1; |
geky | 0:c741e144517c | 51 | } |
geky | 0:c741e144517c | 52 | } |
geky | 0:c741e144517c | 53 | |
geky | 4:38acbd6f9d9e | 54 | void ATParser::flush() { |
geky | 0:c741e144517c | 55 | while (_serial->readable()) |
geky | 0:c741e144517c | 56 | _serial->getc(); |
geky | 0:c741e144517c | 57 | } |
geky | 0:c741e144517c | 58 | |
geky | 7:d1b193880af1 | 59 | |
geky | 6:51f1171b5ebc | 60 | // read/write handling with timeouts |
geky | 6:51f1171b5ebc | 61 | int ATParser::write(const char *data, int size) { |
geky | 6:51f1171b5ebc | 62 | int i; |
geky | 6:51f1171b5ebc | 63 | for (i = 0; i < size; i++) { |
geky | 6:51f1171b5ebc | 64 | if (putc(data[i]) < 0) |
geky | 9:9bcb87c27208 | 65 | return -1; |
geky | 6:51f1171b5ebc | 66 | } |
geky | 6:51f1171b5ebc | 67 | |
geky | 6:51f1171b5ebc | 68 | return i; |
geky | 6:51f1171b5ebc | 69 | } |
geky | 6:51f1171b5ebc | 70 | |
geky | 6:51f1171b5ebc | 71 | int ATParser::read(char *data, int size) { |
geky | 6:51f1171b5ebc | 72 | int i; |
geky | 6:51f1171b5ebc | 73 | for (i = 0; i < size; i++) { |
geky | 6:51f1171b5ebc | 74 | int c = getc(); |
geky | 6:51f1171b5ebc | 75 | if (c < 0) |
geky | 9:9bcb87c27208 | 76 | return -1; |
geky | 6:51f1171b5ebc | 77 | |
geky | 6:51f1171b5ebc | 78 | data[i] = c; |
geky | 6:51f1171b5ebc | 79 | } |
geky | 6:51f1171b5ebc | 80 | |
geky | 6:51f1171b5ebc | 81 | return i; |
geky | 6:51f1171b5ebc | 82 | } |
geky | 6:51f1171b5ebc | 83 | |
geky | 1:66a14afe650a | 84 | |
geky | 9:9bcb87c27208 | 85 | // printf/scanf handling |
geky | 9:9bcb87c27208 | 86 | int ATParser::vprintf(const char *format, va_list args) { |
geky | 9:9bcb87c27208 | 87 | if (vsprintf(_buffer, format, args) < 0) |
geky | 9:9bcb87c27208 | 88 | return false; |
geky | 9:9bcb87c27208 | 89 | |
geky | 9:9bcb87c27208 | 90 | int i; |
geky | 9:9bcb87c27208 | 91 | for (i = 0; _buffer[i]; i++) { |
geky | 9:9bcb87c27208 | 92 | if (putc(_buffer[i]) < 0) |
geky | 9:9bcb87c27208 | 93 | return -1; |
geky | 9:9bcb87c27208 | 94 | } |
geky | 9:9bcb87c27208 | 95 | |
geky | 9:9bcb87c27208 | 96 | return i; |
geky | 9:9bcb87c27208 | 97 | } |
geky | 9:9bcb87c27208 | 98 | |
geky | 9:9bcb87c27208 | 99 | int ATParser::vscanf(const char *format, va_list args) { |
geky | 9:9bcb87c27208 | 100 | // Since format is const, we need to copy it into our buffer to |
geky | 9:9bcb87c27208 | 101 | // add the line's null terminator and clobber value-matches with asterisks. |
geky | 9:9bcb87c27208 | 102 | // |
geky | 9:9bcb87c27208 | 103 | // We just use the beginning of the buffer to avoid unnecessary allocations. |
geky | 9:9bcb87c27208 | 104 | int i = 0; |
geky | 9:9bcb87c27208 | 105 | int offset = 0; |
geky | 9:9bcb87c27208 | 106 | |
geky | 9:9bcb87c27208 | 107 | while (format[i]) { |
geky | 9:9bcb87c27208 | 108 | if (format[i] == '%' && |
geky | 9:9bcb87c27208 | 109 | format[i+1] != '%' && |
geky | 9:9bcb87c27208 | 110 | format[i+1] != '*') { |
geky | 9:9bcb87c27208 | 111 | _buffer[offset++] = '%'; |
geky | 9:9bcb87c27208 | 112 | _buffer[offset++] = '*'; |
geky | 9:9bcb87c27208 | 113 | i++; |
geky | 9:9bcb87c27208 | 114 | } else { |
geky | 9:9bcb87c27208 | 115 | _buffer[offset++] = format[i++]; |
geky | 9:9bcb87c27208 | 116 | } |
geky | 9:9bcb87c27208 | 117 | } |
geky | 9:9bcb87c27208 | 118 | |
geky | 9:9bcb87c27208 | 119 | // Scanf has very poor support for catching errors |
geky | 9:9bcb87c27208 | 120 | // fortunately, we can abuse the %n specifier to determine |
geky | 9:9bcb87c27208 | 121 | // if the entire string was matched. |
geky | 9:9bcb87c27208 | 122 | _buffer[offset++] = '%'; |
geky | 9:9bcb87c27208 | 123 | _buffer[offset++] = 'n'; |
geky | 9:9bcb87c27208 | 124 | _buffer[offset++] = 0; |
geky | 9:9bcb87c27208 | 125 | |
geky | 9:9bcb87c27208 | 126 | // To workaround scanf's lack of error reporting, we actually |
geky | 9:9bcb87c27208 | 127 | // make two passes. One checks the validity with the modified |
geky | 9:9bcb87c27208 | 128 | // format string that only stores the matched characters (%n). |
geky | 9:9bcb87c27208 | 129 | // The other reads in the actual matched values. |
geky | 9:9bcb87c27208 | 130 | // |
geky | 9:9bcb87c27208 | 131 | // We keep trying the match until we succeed or some other error |
geky | 9:9bcb87c27208 | 132 | // derails us. |
geky | 9:9bcb87c27208 | 133 | int j = 0; |
geky | 9:9bcb87c27208 | 134 | |
geky | 9:9bcb87c27208 | 135 | while (true) { |
geky | 9:9bcb87c27208 | 136 | // Ran out of space |
geky | 9:9bcb87c27208 | 137 | if (j+1 >= _buffer_size - offset) |
geky | 9:9bcb87c27208 | 138 | return false; |
geky | 9:9bcb87c27208 | 139 | |
geky | 9:9bcb87c27208 | 140 | // Recieve next character |
geky | 9:9bcb87c27208 | 141 | int c = getc(); |
geky | 9:9bcb87c27208 | 142 | if (c < 0) |
geky | 9:9bcb87c27208 | 143 | return -1; |
geky | 9:9bcb87c27208 | 144 | |
geky | 9:9bcb87c27208 | 145 | _buffer[offset + j++] = c; |
geky | 9:9bcb87c27208 | 146 | _buffer[offset + j] = 0; |
geky | 9:9bcb87c27208 | 147 | |
geky | 9:9bcb87c27208 | 148 | // Check for match |
geky | 9:9bcb87c27208 | 149 | int count = -1; |
geky | 9:9bcb87c27208 | 150 | sscanf(_buffer+offset, _buffer, &count); |
geky | 9:9bcb87c27208 | 151 | |
geky | 9:9bcb87c27208 | 152 | // We only succeed if all characters in the response are matched |
geky | 9:9bcb87c27208 | 153 | if (count == j) { |
geky | 9:9bcb87c27208 | 154 | // Store the found results |
geky | 9:9bcb87c27208 | 155 | vsscanf(_buffer+offset, format, args); |
geky | 9:9bcb87c27208 | 156 | return j; |
geky | 9:9bcb87c27208 | 157 | } |
geky | 9:9bcb87c27208 | 158 | } |
geky | 9:9bcb87c27208 | 159 | } |
geky | 9:9bcb87c27208 | 160 | |
geky | 9:9bcb87c27208 | 161 | |
geky | 7:d1b193880af1 | 162 | // Command parsing with line handling |
geky | 7:d1b193880af1 | 163 | bool ATParser::vsend(const char *command, va_list args) { |
geky | 7:d1b193880af1 | 164 | // Create and send command |
geky | 7:d1b193880af1 | 165 | if (vsprintf(_buffer, command, args) < 0) |
geky | 7:d1b193880af1 | 166 | return false; |
geky | 7:d1b193880af1 | 167 | |
geky | 7:d1b193880af1 | 168 | for (int i = 0; _buffer[i]; i++) { |
geky | 7:d1b193880af1 | 169 | if (putc(_buffer[i]) < 0) |
geky | 0:c741e144517c | 170 | return false; |
geky | 0:c741e144517c | 171 | } |
geky | 0:c741e144517c | 172 | |
geky | 0:c741e144517c | 173 | // Finish with newline |
geky | 3:32915b9467d2 | 174 | for (int i = 0; _delimiter[i]; i++) { |
geky | 4:38acbd6f9d9e | 175 | if (putc(_delimiter[i]) < 0) |
geky | 3:32915b9467d2 | 176 | return false; |
geky | 3:32915b9467d2 | 177 | } |
geky | 0:c741e144517c | 178 | |
geky | 0:c741e144517c | 179 | #ifdef AT_ECHO |
geky | 9:9bcb87c27208 | 180 | ::printf("AT> %s\r\n", _buffer); |
geky | 0:c741e144517c | 181 | #endif |
geky | 5:26bc9255b751 | 182 | |
geky | 5:26bc9255b751 | 183 | return true; |
geky | 5:26bc9255b751 | 184 | } |
geky | 5:26bc9255b751 | 185 | |
geky | 5:26bc9255b751 | 186 | bool ATParser::vrecv(const char *response, va_list args) { |
geky | 1:66a14afe650a | 187 | // Iterate through each line in the expected response |
geky | 5:26bc9255b751 | 188 | while (response[0]) { |
geky | 1:66a14afe650a | 189 | // Since response is const, we need to copy it into our buffer to |
geky | 7:d1b193880af1 | 190 | // add the line's null terminator and clobber value-matches with asterisks. |
geky | 1:66a14afe650a | 191 | // |
geky | 7:d1b193880af1 | 192 | // We just use the beginning of the buffer to avoid unnecessary allocations. |
geky | 1:66a14afe650a | 193 | int i = 0; |
geky | 1:66a14afe650a | 194 | int offset = 0; |
geky | 1:66a14afe650a | 195 | |
geky | 1:66a14afe650a | 196 | while (response[i]) { |
geky | 5:26bc9255b751 | 197 | if (memcmp(&response[i+1-_delim_size], _delimiter, _delim_size) == 0) { |
geky | 5:26bc9255b751 | 198 | i++; |
geky | 1:66a14afe650a | 199 | break; |
geky | 1:66a14afe650a | 200 | } else if (response[i] == '%' && |
geky | 1:66a14afe650a | 201 | response[i+1] != '%' && |
geky | 1:66a14afe650a | 202 | response[i+1] != '*') { |
geky | 1:66a14afe650a | 203 | _buffer[offset++] = '%'; |
geky | 1:66a14afe650a | 204 | _buffer[offset++] = '*'; |
geky | 3:32915b9467d2 | 205 | i++; |
geky | 1:66a14afe650a | 206 | } else { |
geky | 1:66a14afe650a | 207 | _buffer[offset++] = response[i++]; |
geky | 1:66a14afe650a | 208 | } |
geky | 1:66a14afe650a | 209 | } |
geky | 1:66a14afe650a | 210 | |
geky | 1:66a14afe650a | 211 | // Scanf has very poor support for catching errors |
geky | 1:66a14afe650a | 212 | // fortunately, we can abuse the %n specifier to determine |
geky | 1:66a14afe650a | 213 | // if the entire string was matched. |
geky | 1:66a14afe650a | 214 | _buffer[offset++] = '%'; |
geky | 1:66a14afe650a | 215 | _buffer[offset++] = 'n'; |
geky | 1:66a14afe650a | 216 | _buffer[offset++] = 0; |
geky | 1:66a14afe650a | 217 | |
geky | 1:66a14afe650a | 218 | // To workaround scanf's lack of error reporting, we actually |
geky | 1:66a14afe650a | 219 | // make two passes. One checks the validity with the modified |
geky | 1:66a14afe650a | 220 | // format string that only stores the matched characters (%n). |
geky | 1:66a14afe650a | 221 | // The other reads in the actual matched values. |
geky | 1:66a14afe650a | 222 | // |
geky | 1:66a14afe650a | 223 | // We keep trying the match until we succeed or some other error |
geky | 1:66a14afe650a | 224 | // derails us. |
geky | 7:d1b193880af1 | 225 | int j = 0; |
geky | 7:d1b193880af1 | 226 | |
geky | 9:9bcb87c27208 | 227 | while (true) { |
geky | 9:9bcb87c27208 | 228 | // Ran out of space |
geky | 9:9bcb87c27208 | 229 | if (j+1 >= _buffer_size - offset) |
geky | 9:9bcb87c27208 | 230 | return false; |
geky | 9:9bcb87c27208 | 231 | |
geky | 7:d1b193880af1 | 232 | // Recieve next character |
geky | 7:d1b193880af1 | 233 | int c = getc(); |
geky | 7:d1b193880af1 | 234 | if (c < 0) |
geky | 1:66a14afe650a | 235 | return false; |
geky | 7:d1b193880af1 | 236 | |
geky | 7:d1b193880af1 | 237 | _buffer[offset + j++] = c; |
geky | 7:d1b193880af1 | 238 | _buffer[offset + j] = 0; |
geky | 7:d1b193880af1 | 239 | |
geky | 7:d1b193880af1 | 240 | // Check for match |
geky | 2:4d68f546861c | 241 | int count = -1; |
geky | 1:66a14afe650a | 242 | sscanf(_buffer+offset, _buffer, &count); |
geky | 1:66a14afe650a | 243 | |
geky | 7:d1b193880af1 | 244 | // We only succeed if all characters in the response are matched |
geky | 7:d1b193880af1 | 245 | if (count == j) { |
geky | 7:d1b193880af1 | 246 | #ifdef AT_ECHO |
geky | 9:9bcb87c27208 | 247 | ::printf("AT= %s\r\n", _buffer+offset); |
geky | 7:d1b193880af1 | 248 | #endif |
geky | 1:66a14afe650a | 249 | // Reuse the front end of the buffer |
geky | 6:51f1171b5ebc | 250 | memcpy(_buffer, response, i); |
geky | 6:51f1171b5ebc | 251 | _buffer[i] = 0; |
geky | 1:66a14afe650a | 252 | |
geky | 1:66a14afe650a | 253 | // Store the found results |
geky | 1:66a14afe650a | 254 | vsscanf(_buffer+offset, _buffer, args); |
geky | 1:66a14afe650a | 255 | |
geky | 1:66a14afe650a | 256 | // Jump to next line and continue parsing |
geky | 1:66a14afe650a | 257 | response += i; |
geky | 1:66a14afe650a | 258 | break; |
geky | 1:66a14afe650a | 259 | } |
geky | 7:d1b193880af1 | 260 | |
geky | 7:d1b193880af1 | 261 | // Clear the buffer when we hit a newline |
geky | 7:d1b193880af1 | 262 | if (strcmp(&_buffer[offset + j-_delim_size], _delimiter) == 0) { |
geky | 7:d1b193880af1 | 263 | #ifdef AT_ECHO |
geky | 9:9bcb87c27208 | 264 | ::printf("AT< %s", _buffer+offset); |
geky | 7:d1b193880af1 | 265 | #endif |
geky | 7:d1b193880af1 | 266 | j = 0; |
geky | 7:d1b193880af1 | 267 | } |
geky | 1:66a14afe650a | 268 | } |
geky | 0:c741e144517c | 269 | } |
geky | 5:26bc9255b751 | 270 | |
geky | 5:26bc9255b751 | 271 | return true; |
geky | 5:26bc9255b751 | 272 | } |
geky | 5:26bc9255b751 | 273 | |
geky | 7:d1b193880af1 | 274 | |
geky | 5:26bc9255b751 | 275 | // Mapping to vararg functions |
geky | 9:9bcb87c27208 | 276 | int ATParser::printf(const char *format, ...) { |
geky | 9:9bcb87c27208 | 277 | va_list args; |
geky | 9:9bcb87c27208 | 278 | va_start(args, format); |
geky | 9:9bcb87c27208 | 279 | int res = vprintf(format, args); |
geky | 9:9bcb87c27208 | 280 | va_end(args); |
geky | 9:9bcb87c27208 | 281 | return res; |
geky | 9:9bcb87c27208 | 282 | } |
geky | 9:9bcb87c27208 | 283 | |
geky | 9:9bcb87c27208 | 284 | int ATParser::scanf(const char *format, ...) { |
geky | 9:9bcb87c27208 | 285 | va_list args; |
geky | 9:9bcb87c27208 | 286 | va_start(args, format); |
geky | 9:9bcb87c27208 | 287 | int res = vscanf(format, args); |
geky | 9:9bcb87c27208 | 288 | va_end(args); |
geky | 9:9bcb87c27208 | 289 | return res; |
geky | 9:9bcb87c27208 | 290 | } |
geky | 9:9bcb87c27208 | 291 | |
geky | 5:26bc9255b751 | 292 | bool ATParser::send(const char *command, ...) { |
geky | 5:26bc9255b751 | 293 | va_list args; |
geky | 5:26bc9255b751 | 294 | va_start(args, command); |
geky | 5:26bc9255b751 | 295 | bool res = vsend(command, args); |
geky | 5:26bc9255b751 | 296 | va_end(args); |
geky | 5:26bc9255b751 | 297 | return res; |
geky | 5:26bc9255b751 | 298 | } |
geky | 5:26bc9255b751 | 299 | |
geky | 5:26bc9255b751 | 300 | bool ATParser::recv(const char *response, ...) { |
geky | 5:26bc9255b751 | 301 | va_list args; |
geky | 5:26bc9255b751 | 302 | va_start(args, response); |
geky | 5:26bc9255b751 | 303 | bool res = vrecv(response, args); |
geky | 5:26bc9255b751 | 304 | va_end(args); |
geky | 5:26bc9255b751 | 305 | return res; |
geky | 5:26bc9255b751 | 306 | } |