Gabe/learning_c
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

added comments to document non-obvious things.

Browse source
This commit is contained in:
Gabe Venberg 2023-09-13 13:11:17 -05:00
parent ae1e7979c7
commit 2599bbb6b8
1 changed files with 15 additions and 29 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

44
serial_logger/src/serial_logger.c
View file

@ -11,12 +11,14 @@
#include <unistd.h> #include <unistd.h>
static const char doc[] = static const char doc[] =
"Reads a serial terminal and outputs to a log file while also printing contents.\n" "Reads a serial terminal and outputs to a log file while also printing "
"contents.\n"
"Any options that have a negation as well as an assertion will use " "Any options that have a negation as well as an assertion will use "
"defaults for the provided tty if neither is provided.\n" "defaults for the provided tty if neither is provided.\n"
"If LOG_FILE is not given, will only output to stdout"; "If LOG_FILE is not given, will only output to stdout";
static const char args_doc[] = "INPUT_FILE"; static const char args_doc[] = "INPUT_FILE";
// for the parsed CLI args, we want to know if the user explicitly set them, because if not, we dont want to touch them.
typedef enum { TRUE, FALSE, DEFAULT } OptionalBool; typedef enum { TRUE, FALSE, DEFAULT } OptionalBool;
// starts at 128 to make sure none of them are ascii printable. // starts at 128 to make sure none of them are ascii printable.
@ -31,6 +33,7 @@ typedef enum {
NO_IGNCR NO_IGNCR
} longOnlyOpts; } longOnlyOpts;
// for storing the parsed CLI args.
struct Arguments { struct Arguments {
char* inFile; char* inFile;
char* logFile; char* logFile;
@ -57,7 +60,8 @@ static struct argp_option options[] = {
{"igncr", ENABLE_IGNCR, 0, 0, "ignore cr", 0}, {"igncr", ENABLE_IGNCR, 0, 0, "ignore cr", 0},
{"no-igncr", NO_IGNCR, 0, 0, "do not ignore cr", 0}, {"no-igncr", NO_IGNCR, 0, 0, "do not ignore cr", 0},
{"baud-rate", 'r', "BAUDRATE", 0, {"baud-rate", 'r', "BAUDRATE", 0,
"baud rate of the terminal.\nMust be a standard baud rate: 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, " "baud rate of the terminal.\nMust be a standard baud rate: 50, 75, 110, "
" 134, 150, 200, 300, 600, 1200, 1800, "
"2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400, or 460800", "2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400, or 460800",
0}, 0},
{0}, {0},
@ -129,23 +133,6 @@ static error_t parseArgs(int key, char* arg, struct argp_state* state) {
static struct argp argp = {options, parseArgs, args_doc, doc, 0, 0, 0}; static struct argp argp = {options, parseArgs, args_doc, doc, 0, 0, 0};
// static bool parseArgs(int argc, char* argv[], struct Arguments* arguments) {
// bool succsess = true;
// switch (argc) {
// case 3:
// arguments->logFile = argv[2];
// // fallthrough
// case 2:
// arguments->inFile = argv[1];
// break;
// default:
// printf("%s\n%s\n", args_doc, doc);
// succsess = false;
// break;
// }
// return succsess;
// }
// puts the current time into buff in the form of YYYY-MM-DD HH:MM:SS. // puts the current time into buff in the form of YYYY-MM-DD HH:MM:SS.
// buff MUST BE at least 20 chars long. // buff MUST BE at least 20 chars long.
static bool getTimeString(char* buff) { static bool getTimeString(char* buff) {
@ -164,6 +151,7 @@ static bool getTimeString(char* buff) {
return succsess; return succsess;
} }
// puts the given string into the logfile alongside a basic timestamp.
static bool sendToLog(FILE* logFile, char* lineBuff) { static bool sendToLog(FILE* logFile, char* lineBuff) {
bool succsess = true; bool succsess = true;
char currentTime[20] = ""; char currentTime[20] = "";
@ -367,12 +355,16 @@ static bool setTTY(struct termios* tty, struct Arguments* arguments) {
return success; return success;
} }
static bool initInputFile(FILE** inFile, struct Arguments* arguments) { // opens the TTY file, and applies any options to the tty through termios that are non-DEFAULT in arguments.
static bool initTTY(FILE** inFile, struct Arguments* arguments) {
bool succsess = true; bool succsess = true;
*inFile = fopen(arguments->inFile, "r"); *inFile = fopen(arguments->inFile, "r");
// the tcgetattr and dcsetattr require POSIX file descriptors, but our reading and writing functions require file
// pointers. (I dont want to re-implement buffered input myself)
int fd = fileno(*inFile); int fd = fileno(*inFile);
if (inFile != NULL || fd >= 0) { if (inFile != NULL || fd >= 0) {
struct termios tty; struct termios tty;
// initalize the tty struct with current settings. This is required by POSIX.
if (tcgetattr(fd, &tty) == 0) { if (tcgetattr(fd, &tty) == 0) {
if (setTTY(&tty, arguments) != 0) { if (setTTY(&tty, arguments) != 0) {
// Save tty settings, also checking for error // Save tty settings, also checking for error
@ -431,23 +423,17 @@ static void processLines(FILE* inFile, FILE* logFile) {
} }
int main(int argc, char* argv[]) { int main(int argc, char* argv[]) {
// for some reason, when doing this with a serial port, log.log never gets
// written to. I think this is becasue the program is terminated with
// ctrl-c, so the file descriptors dont close? adding fflushes fixes it, but
// I shouldnt need to add that.
int ret = EXIT_SUCCESS; int ret = EXIT_SUCCESS;
// an argument that is left DEFAULT will not change the tty from whatever state it was in before the start of the
// program.
static struct Arguments arguments = {NULL, NULL, DEFAULT, DEFAULT, 0, DEFAULT, DEFAULT, DEFAULT, 0}; static struct Arguments arguments = {NULL, NULL, DEFAULT, DEFAULT, 0, DEFAULT, DEFAULT, DEFAULT, 0};
argp_parse(&argp, argc, argv, 0, 0, &arguments); argp_parse(&argp, argc, argv, 0, 0, &arguments);
FILE* inFile = NULL; FILE* inFile = NULL;
if (initInputFile(&inFile, &arguments)) { if (initTTY(&inFile, &arguments)) {
FILE* outFile = NULL; FILE* outFile = NULL;
if (initLogFile(&outFile, arguments.logFile)) { if (initLogFile(&outFile, arguments.logFile)) {
processLines(inFile, outFile); processLines(inFile, outFile);
// these things should be done by the OS when we exit.
// fclose(inFile);
// fclose(outFile);
} else { } else {
ret = EXIT_FAILURE; ret = EXIT_FAILURE;
} }