RTC auf true
platform/ATCmdParser.cpp
- Committer:
- kevman
- Date:
- 2019-03-13
- Revision:
- 2:7aab896b1a3b
- Parent:
- 0:38ceb79fef03
File content as of revision 2:7aab896b1a3b:
/* Copyright (c) 2017 ARM Limited * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * * @section DESCRIPTION * * Parser for the AT command syntax * */ #include "ATCmdParser.h" #include "mbed_poll.h" #include "mbed_debug.h" #ifdef LF #undef LF #define LF 10 #else #define LF 10 #endif #ifdef CR #undef CR #define CR 13 #else #define CR 13 #endif // getc/putc handling with timeouts int ATCmdParser::putc(char c) { pollfh fhs; fhs.fh = _fh; fhs.events = POLLOUT; int count = poll(&fhs, 1, _timeout); if (count > 0 && (fhs.revents & POLLOUT)) { return _fh->write(&c, 1) == 1 ? 0 : -1; } else { return -1; } } int ATCmdParser::getc() { pollfh fhs; fhs.fh = _fh; fhs.events = POLLIN; int count = poll(&fhs, 1, _timeout); if (count > 0 && (fhs.revents & POLLIN)) { unsigned char ch; return _fh->read(&ch, 1) == 1 ? ch : -1; } else { return -1; } } void ATCmdParser::flush() { while (_fh->readable()) { unsigned char ch; _fh->read(&ch, 1); } } // read/write handling with timeouts int ATCmdParser::write(const char *data, int size) { int i = 0; for (; i < size; i++) { if (putc(data[i]) < 0) { return -1; } } return i; } int ATCmdParser::read(char *data, int size) { int i = 0; for (; i < size; i++) { int c = getc(); if (c < 0) { return -1; } data[i] = c; } return i; } // printf/scanf handling int ATCmdParser::vprintf(const char *format, va_list args) { if (vsprintf(_buffer, format, args) < 0) { return false; } int i = 0; for (; _buffer[i]; i++) { if (putc(_buffer[i]) < 0) { return -1; } } return i; } int ATCmdParser::vscanf(const char *format, va_list args) { // Since format is const, we need to copy it into our buffer to // add the line's null terminator and clobber value-matches with asterisks. // // We just use the beginning of the buffer to avoid unnecessary allocations. int i = 0; int offset = 0; while (format[i]) { if (format[i] == '%' && format[i + 1] != '%' && format[i + 1] != '*') { _buffer[offset++] = '%'; _buffer[offset++] = '*'; i++; } else { _buffer[offset++] = format[i++]; } } // Scanf has very poor support for catching errors // fortunately, we can abuse the %n specifier to determine // if the entire string was matched. _buffer[offset++] = '%'; _buffer[offset++] = 'n'; _buffer[offset++] = 0; // To workaround scanf's lack of error reporting, we actually // make two passes. One checks the validity with the modified // format string that only stores the matched characters (%n). // The other reads in the actual matched values. // // We keep trying the match until we succeed or some other error // derails us. int j = 0; while (true) { // Ran out of space if (j + 1 >= _buffer_size - offset) { return false; } // Receive next character int c = getc(); if (c < 0) { return -1; } _buffer[offset + j++] = c; _buffer[offset + j] = 0; // Check for match int count = -1; sscanf(_buffer + offset, _buffer, &count); // We only succeed if all characters in the response are matched if (count == j) { // Store the found results vsscanf(_buffer + offset, format, args); return j; } } } // Command parsing with line handling bool ATCmdParser::vsend(const char *command, va_list args) { // Create and send command if (vsprintf(_buffer, command, args) < 0) { return false; } for (int i = 0; _buffer[i]; i++) { if (putc(_buffer[i]) < 0) { return false; } } // Finish with newline for (size_t i = 0; _output_delimiter[i]; i++) { if (putc(_output_delimiter[i]) < 0) { return false; } } debug_if(_dbg_on, "AT> %s\n", _buffer); return true; } bool ATCmdParser::vrecv(const char *response, va_list args) { restart: _aborted = false; // Iterate through each line in the expected response // response being NULL means we just want to check for OOBs while (!response || response[0]) { // Since response is const, we need to copy it into our buffer to // add the line's null terminator and clobber value-matches with asterisks. // // We just use the beginning of the buffer to avoid unnecessary allocations. int i = 0; int offset = 0; bool whole_line_wanted = false; while (response && response[i]) { if (response[i] == '%' && response[i + 1] != '%' && response[i + 1] != '*') { _buffer[offset++] = '%'; _buffer[offset++] = '*'; i++; } else { _buffer[offset++] = response[i++]; // Find linebreaks, taking care not to be fooled if they're in a %[^\n] conversion specification if (response[i - 1] == '\n' && !(i >= 3 && response[i - 3] == '[' && response[i - 2] == '^')) { whole_line_wanted = true; break; } } } // Scanf has very poor support for catching errors // fortunately, we can abuse the %n specifier to determine // if the entire string was matched. _buffer[offset++] = '%'; _buffer[offset++] = 'n'; _buffer[offset++] = 0; debug_if(_dbg_on, "AT? %s\n", _buffer); // To workaround scanf's lack of error reporting, we actually // make two passes. One checks the validity with the modified // format string that only stores the matched characters (%n). // The other reads in the actual matched values. // // We keep trying the match until we succeed or some other error // derails us. int j = 0; while (true) { // If just peeking for OOBs, and at start of line, check // readability if (!response && j == 0 && !_fh->readable()) { return false; } // Receive next character int c = getc(); if (c < 0) { debug_if(_dbg_on, "AT(Timeout)\n"); return false; } // Simplify newlines (borrowed from retarget.cpp) if ((c == CR && _in_prev != LF) || (c == LF && _in_prev != CR)) { _in_prev = c; c = '\n'; } else if ((c == CR && _in_prev == LF) || (c == LF && _in_prev == CR)) { _in_prev = c; // onto next character continue; } else { _in_prev = c; } _buffer[offset + j++] = c; _buffer[offset + j] = 0; // Check for oob data for (struct oob *oob = _oobs; oob; oob = oob->next) { if ((unsigned)j == oob->len && memcmp( oob->prefix, _buffer + offset, oob->len) == 0) { debug_if(_dbg_on, "AT! %s\n", oob->prefix); _oob_cb_count++; oob->cb(); if (_aborted) { debug_if(_dbg_on, "AT(Aborted)\n"); return false; } // oob may have corrupted non-reentrant buffer, // so we need to set it up again goto restart; } } // Check for match int count = -1; if (whole_line_wanted && c != '\n') { // Don't attempt scanning until we get delimiter if they included it in format // This allows recv("Foo: %s\n") to work, and not match with just the first character of a string // (scanf does not itself match whitespace in its format string, so \n is not significant to it) } else if (response) { sscanf(_buffer + offset, _buffer, &count); } // We only succeed if all characters in the response are matched if (count == j) { debug_if(_dbg_on, "AT= %s\n", _buffer + offset); // Reuse the front end of the buffer memcpy(_buffer, response, i); _buffer[i] = 0; // Store the found results vsscanf(_buffer + offset, _buffer, args); // Jump to next line and continue parsing response += i; break; } // Clear the buffer when we hit a newline or ran out of space // running out of space usually means we ran into binary data if (c == '\n' || j + 1 >= _buffer_size - offset) { debug_if(_dbg_on, "AT< %s", _buffer + offset); j = 0; } } } return true; } // Mapping to vararg functions int ATCmdParser::printf(const char *format, ...) { va_list args; va_start(args, format); int res = vprintf(format, args); va_end(args); return res; } int ATCmdParser::scanf(const char *format, ...) { va_list args; va_start(args, format); int res = vscanf(format, args); va_end(args); return res; } bool ATCmdParser::send(const char *command, ...) { va_list args; va_start(args, command); bool res = vsend(command, args); va_end(args); return res; } bool ATCmdParser::recv(const char *response, ...) { va_list args; va_start(args, response); bool res = vrecv(response, args); va_end(args); return res; } // oob registration void ATCmdParser::oob(const char *prefix, Callback<void()> cb) { struct oob *oob = new struct oob; oob->len = strlen(prefix); oob->prefix = prefix; oob->cb = cb; oob->next = _oobs; _oobs = oob; } void ATCmdParser::abort() { _aborted = true; } bool ATCmdParser::process_oob() { int pre_count = _oob_cb_count; recv(NULL); return _oob_cb_count != pre_count; }