From 3ca5e4160229cf7d0b389ec8fdf2ec18f6e1aa46 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mario=20H=C3=BCttel?= <mario.huettel@gmx.net>
Date: Fri, 30 Oct 2020 23:12:39 +0100
Subject: [PATCH] Implement config read function

---
 stm-firmware/config-parser/config-parser.c    | 86 ++++++++++++++++++-
 .../include/config-parser/config-parser.h     |  7 +-
 2 files changed, 88 insertions(+), 5 deletions(-)

diff --git a/stm-firmware/config-parser/config-parser.c b/stm-firmware/config-parser/config-parser.c
index 3d15e19..6b58a2d 100644
--- a/stm-firmware/config-parser/config-parser.c
+++ b/stm-firmware/config-parser/config-parser.c
@@ -26,6 +26,7 @@
 #include <config-parser/config-parser.h>
 #include <string.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #define CONFIG_PARSER_MAGIC 0x464a6e2bUL
 #define CONFIG_PARSER(p) ((struct config_parser *)(p))
@@ -36,7 +37,7 @@
 						} while (0)
 
 config_parser_handle_t config_parser_open_file(struct config_parser *config_parser, bool write, const char *file_name,
-					       char *working_buffer)
+					       char *working_buffer, size_t buff_size)
 {
 	FRESULT res;
 
@@ -46,6 +47,7 @@ config_parser_handle_t config_parser_open_file(struct config_parser *config_pars
 	config_parser->magic = CONFIG_PARSER_MAGIC;
 	config_parser->write = write;
 	config_parser->buffer = working_buffer;
+	config_parser->buff_size = buff_size;
 
 	res = f_open(&config_parser->file, file_name, (write ? FA_CREATE_ALWAYS | FA_WRITE : FA_READ));
 	if (res != FR_OK)
@@ -54,10 +56,90 @@ config_parser_handle_t config_parser_open_file(struct config_parser *config_pars
 	return (config_parser_handle_t)config_parser;
 }
 
+static const char * const token_delim = " \t";
+
+static int parse_value(struct config_parser_entry  *entry, char *value_start_token)
+{
+	char *dot;
+	char *endptr;
+
+	/* Check if token is a float number */
+	dot = strstr(value_start_token, ".");
+	if (dot) {
+		/* Try parsing as float */
+		entry->value.float_val = strtof(value_start_token, &endptr);
+		if (endptr == value_start_token)
+			return -1;
+		entry->type = CONFIG_PARSER_TYPE_FLOAT;
+	}
+
+	if (value_start_token[0] != '-') {
+		/* Try parsing as ul */
+		/* Try parsing as int */
+		entry->value.uint_val = strtoul(value_start_token, &endptr, 0);
+		if (endptr == value_start_token) {
+			return -1;
+		}
+		entry->type = CONFIG_PARSER_TYPE_UINT;
+	} else {
+		/* Try parsing as int */
+		entry->value.int_val = strtod(value_start_token, &endptr);
+		if (endptr == value_start_token) {
+			return -1;
+		}
+		entry->type = CONFIG_PARSER_TYPE_INT;
+	}
+
+	return 0;
+}
+
 enum config_parser_ret config_parser_get_line(config_parser_handle_t handle, struct config_parser_entry *entry)
 {
-	(void)entry;
+	struct config_parser *p;
 	config_parser_check_handle(handle);
+	p = CONFIG_PARSER(handle);
+	char *token;
+	int token_round = 0;
+
+	if (!entry)
+		return CONFIG_PARSER_PARAM_ERR;
+
+	p->buffer[0] = '\0';
+	if (f_gets(p->buffer, (int)p->buff_size, &p->file) == NULL)
+		return CONFIG_PARSER_IOERR;
+
+	token = strtok(p->buffer, token_delim);
+	while (token != NULL) {
+		/* Check for comment */
+		if (token[0] == '#') {
+			if (token_round == 0)
+				return CONFIG_PARSER_LINE_COMMENT;
+			else
+				break;
+		}
+
+		switch (token_round) {
+		case 0: /* KEY */
+			entry->name = token;
+			break;
+		case 1: /* = Symbol */
+			if (strcmp(token, "=")) {
+				return CONFIG_PARSER_LINE_MALFORM;
+			}
+			break;
+		case 2: /* VALUE */
+			if (!parse_value(entry, token))
+				return CONFIG_PARSER_LINE_MALFORM;
+			break;
+		default:
+			return CONFIG_PARSER_LINE_MALFORM;
+		}
+
+
+		token_round++;
+		strtok(NULL, token_delim);
+	}
+
 
 	return CONFIG_PARSER_OK;
 }
diff --git a/stm-firmware/config-parser/include/config-parser/config-parser.h b/stm-firmware/config-parser/include/config-parser/config-parser.h
index cf11ba9..e228363 100644
--- a/stm-firmware/config-parser/include/config-parser/config-parser.h
+++ b/stm-firmware/config-parser/include/config-parser/config-parser.h
@@ -29,6 +29,7 @@
 #define _CONFIG_PARSER_H_
 
 #include <stdint.h>
+#include <stddef.h>
 #include <stdbool.h>
 #include <fatfs/ff.h>
 
@@ -37,6 +38,7 @@ struct config_parser {
 	bool write;
 	FIL file;
 	char *buffer;
+	size_t buff_size;
 };
 
 typedef void * config_parser_handle_t;
@@ -44,7 +46,6 @@ typedef void * config_parser_handle_t;
 enum config_parser_value_type {
 	CONFIG_PARSER_TYPE_UINT = 0,
 	CONFIG_PARSER_TYPE_INT,
-	CONFIG_PARSER_TYPE_STRING,
 	CONFIG_PARSER_TYPE_FLOAT,
 };
 
@@ -53,6 +54,7 @@ enum config_parser_ret {
 	CONFIG_PARSER_PARAM_ERR,
 	CONFIG_PARSER_GENERIC_ERR,
 	CONFIG_PARSER_IOERR,
+	CONFIG_PARSER_LINE_COMMENT,
 	CONFIG_PARSER_LINE_TOO_LONG,
 	CONFIG_PARSER_LINE_MALFORM,
 	CONFIG_PARSER_END_REACHED,
@@ -65,13 +67,12 @@ struct config_parser_entry {
 	union {
 		uint32_t uint_val;
 		int32_t int_val;
-		const char *string_val;
 		float float_val;
 	} value;
 };
 
 config_parser_handle_t config_parser_open_file(struct config_parser *config_parser, bool write, const char *file_name,
-					       char *working_buffer);
+					       char *working_buffer, size_t buff_size);
 
 /**
  * @brief Parse the current line in the config file.