ARMmbed
/
mbed-os
mirror of https://github.com/ARMmbed/mbed-os.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

ATCmdParser: merge scanf and recv functions.The goal is to give a configuration parameter for this function which would indicate are we trying to find a match from one line(scanf) or do we might end up processing multiple lines(recv) to find a match.

pull/11720/head
Marcin Tomczyk 2019-10-21 10:18:23 +02:00
parent 1798c246cc
commit 15eb2a6e4f
2 changed files with 61 additions and 81 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
platform/ATCmdParser.h
View File

@ -79,6 +79,24 @@ private:
};
oob *_oobs;
/**
* Receive an AT response
*
* Receives a formatted response using scanf style formatting
* @see scanf
*
* Responses are parsed line at a time.
* If multiline is set to false parse only one line otherwise parse multiline response
* Any received data that does not match the response is ignored until
* a timeout occurs.
*
* @param response scanf-like format string of response to expect
* @param ... all scanf-like arguments to extract from response
* @param multiline determinate if parse one or multiple lines.
* @return number of bytes read or -1 on failure
*/
int vrecvscanf(const char *response, std::va_list args, bool multiline);
public:
/**

124
platform/source/ATCmdParser.cpp
View File

@ -124,68 +124,6 @@ int ATCmdParser::vprintf(const char *format, std::va_list args)
return i;
}
int ATCmdParser::vscanf(const char *format, std::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, std::va_list args)
{
@ -211,7 +149,7 @@ bool ATCmdParser::vsend(const char *command, std::va_list args)
return true;
}
bool ATCmdParser::vrecv(const char *response, std::va_list args)
int ATCmdParser::vrecvscanf(const char *response, std::va_list args, bool multiline)
{
restart:
_aborted = false;
@ -259,17 +197,24 @@ restart:
int j = 0;
while (true) {
// Ran out of space
if (j + 1 >= _buffer_size - offset) {
return -1;
}
// If just peeking for OOBs, and at start of line, check
// readability
if (!response && j == 0 && !_fh->readable()) {
return false;
return -1;
}
// Receive next character
int c = getc();
if (c < 0) {
debug_if(_dbg_on, "AT(Timeout)\n");
return false;
return -1;
}
// Simplify newlines (borrowed from retarget.cpp)
if ((c == CR && _in_prev != LF) ||
(c == LF && _in_prev != CR)) {
@ -283,24 +228,27 @@ restart:
} 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 (multiline) {
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;
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;
}
// oob may have corrupted non-reentrant buffer,
// so we need to set it up again
goto restart;
}
}
@ -323,6 +271,10 @@ restart:
// Store the found results
vsscanf(_buffer + offset, _buffer, args);
if (!multiline) {
return j;
}
// Jump to next line and continue parsing
response += i;
break;
@ -337,7 +289,17 @@ restart:
}
}
return true;
return 1;
}
int ATCmdParser::vscanf(const char *format, std::va_list args)
{
return vrecvscanf(format, args, false);
}
bool ATCmdParser::vrecv(const char *response, std::va_list args)
{
return (vrecvscanf(response, args, true)) > 0 ? true : false;
}
// Mapping to vararg functions
@ -354,7 +316,7 @@ int ATCmdParser::scanf(const char *format, ...)
{
std::va_list args;
va_start(args, format);
int res = vscanf(format, args);
int res = vrecvscanf(format, args, false);
va_end(args);
return res;
}
@ -372,9 +334,9 @@ bool ATCmdParser::recv(const char *response, ...)
{
std::va_list args;
va_start(args, response);
bool res = vrecv(response, args);
int res = vrecvscanf(response, args, true);
va_end(args);
return res;
return (res > 0) ? true : false;
}
// oob registration