frugen: Add an option to force ASCII encoding

It is now possible to disable text encoding autodetection
and force ASCII 8-bit encoding.

To do so with libfru, use `fru_set_autodetect(false)`.

To do so with frugen, use `frugen -A` or `frugen --ascii`.

Partially resolves #11
Signed-off-by: Alexander Amelkin <a.amelkin@yadro.com>

fru.c

@@ -37,6 +37,13 @@
 #define DEBUG(f, args...)
 #endif
 
+static bool autodetect = true;
+
+void fru_set_autodetect(bool enable)
+{
+	autodetect = enable;
+}
+
 /**
  * Strip trailing spaces
  */
@@ -92,10 +99,15 @@ uint8_t fru_get_typelen(int len,             /**< [in] Length of the data or LEN
 
 	// As we reach this point, we know the data must be text.
 	// We will try to find the encoding that suits best.
+	if (autodetect) {
+		typelen = FRU_TYPELEN(BCDPLUS, (len + 1) / 2); // By default - the most range-restricted text type
 
-	typelen = FRU_TYPELEN(BCDPLUS, (len + 1) / 2); // By default - the most range-restricted text type
-
-	DEBUG("Assuming BCD plus data...\n");
+		DEBUG("Assuming BCD plus data...\n");
+	}
+	else {
+		DEBUG("Assuming ASCII data...\n");
+		typelen = FRU_TYPELEN(TEXT, len);
+	}
 
 	// Go through the data and expand charset as needed
 	for (i = 0; i < len; i++) {
@@ -112,22 +124,24 @@ uint8_t fru_get_typelen(int len,             /**< [in] Length of the data or LEN
 			break;
 		}
 
-		if (typelen < FRU_MAKETYPE(TEXT)
-			&& (data[i] > '_' || data[i] < ' '))
-		{ // Do not reduce the range
-			// The data doesn't fit into 6-bit ASCII, expand to simple text.
-			DEBUG("[%c] Data is simple text!\n", data[i]);
-			typelen = FRU_TYPELEN(TEXT, len);
-			continue;
-		}
+		if (autodetect) {
+			if (typelen < FRU_MAKETYPE(TEXT)
+				&& (data[i] > '_' || data[i] < ' '))
+			{ // Do not reduce the range
+				// The data doesn't fit into 6-bit ASCII, expand to simple text.
+				DEBUG("[%c] Data is simple text!\n", data[i]);
+				typelen = FRU_TYPELEN(TEXT, len);
+				continue;
+			}
 
-		if (typelen < FRU_MAKETYPE(ASCII_6BIT) && // Do not reduce the range
-		    !isdigit(data[i]) && data[i] != ' ' && data[i] != '-' && data[i] != '.')
-		{
-			// The data doesn't fit into BCD plus, expand to
-			DEBUG("[%c] Data is 6-bit ASCII!\n", data[i]);
-			typelen = FRU_TYPELEN(ASCII_6BIT, FRU_6BIT_LENGTH(len));
-		}
+			if (typelen < FRU_MAKETYPE(ASCII_6BIT) && // Do not reduce the range
+			    !isdigit(data[i]) && data[i] != ' ' && data[i] != '-' && data[i] != '.')
+			{
+				// The data doesn't fit into BCD plus, expand to
+				DEBUG("[%c] Data is 6-bit ASCII!\n", data[i]);
+				typelen = FRU_TYPELEN(ASCII_6BIT, FRU_6BIT_LENGTH(len));
+			}
+		} /* autodetect */
 	}
 
 	return typelen;

fru.h

@@ -8,6 +8,7 @@
 #ifndef __FRULIB_FRU_H__
 #define __FRULIB_FRU_H__
 
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
@@ -300,6 +301,8 @@ typedef struct {
 
 #define fru_loadfield(eafield, value) strncpy(eafield, value, FRU_FIELDMAXLEN)
 
+void fru_set_autodetect(bool enable);
+
 fru_chassis_area_t * fru_chassis_info(const fru_exploded_chassis_t *chassis);
 fru_board_area_t * fru_board_info(const fru_exploded_board_t *board);
 fru_product_area_t * fru_product_info(const fru_exploded_product_t *product);

frugen.c

@@ -378,6 +378,11 @@ int main(int argc, char *argv[])
 		/* Mark the following '*-custom' data as binary */
 		{ .name = "binary",        .val = 'b', .has_arg = false },
 
+		/* Disable autodetection, force ASCII encoding on standard fields,
+		 * Detection of binary (out of ASCII range) stays in place.
+		 */
+		{ .name = "ascii",         .val = 'I', .has_arg = false },
+
 		/* Set input file format to JSON */
 		{ .name = "json",          .val = 'j', .has_arg = false },
 
@@ -420,6 +425,8 @@ int main(int argc, char *argv[])
 			    "Example: frugen --binary --board-custom 0012DEADBEAF\n"
 			    "\n\t\t"
 			    "There must be an even number of characters in a 'binary' argument",
+		['I'] = "Disable auto-encoding on all fields, force ASCII.\n\t\t"
+			    "Out of ASCII range data will still result in binary encoding.",
 		['j'] = "Set input text file format to JSON (default). Specify before '--from'",
 		['z'] = "Load FRU information from a text file",
 		/* Chassis info area related options */
@@ -479,6 +486,9 @@ int main(int argc, char *argv[])
 				debug(2, "Next custom field will be considered binary");
 				cust_binary = true;
 				break;
+			case 'I': // ASCII
+				fru_set_autodetect(false);
+				break;
 			case 'v': // verbose
 				debug_level++;
 				debug(debug_level, "Verbosity level set to %d", debug_level);