input: Controller unique mapping (preliminary)

Add ini option `unique_mapping` which makes controller mappings unique to the physical port the controller is connected to.
Calculates a uint32_t unique_hash for each device during enumeration.

Co-authored-by: Martin Donlon <github-martin@donlons.com>

cfg.cpp

@@ -119,6 +119,7 @@ static const ini_var_t ini_vars[] =
 	{ "HDR_AVG_NITS", (void*)(&(cfg.hdr_avg_nits)), UINT16, 100, 10000},
 	{ "VGA_MODE", (void*)(&(cfg.vga_mode)), STRING, 0, sizeof(cfg.vga_mode) - 1 },
 	{ "NTSC_MODE", (void *)(&(cfg.ntsc_mode)), UINT8, 0, 2},
+	{ "UNIQUE_MAPPING", (void *)(&(cfg.unique_mapping)), UINT8, 0, 1},
 };
 
 static const int nvars = (int)(sizeof(ini_vars) / sizeof(ini_var_t));

cfg.h

@@ -91,6 +91,7 @@ typedef struct {
 	char vga_mode[16];
 	char vga_mode_int;
 	char ntsc_mode;
+	uint8_t unique_mapping;
 } cfg_t;
 
 extern cfg_t cfg;

input.cpp

@@ -30,6 +30,7 @@
 #include "support.h"
 #include "profiling.h"
 #include "gamecontroller_db.h"
+#include "str_util.h"
 
 #define NUMDEV 30
 #define NUMPLAYERS 6
@@ -1189,6 +1190,7 @@ typedef struct
 	char     mac[64];
 
 	int      bind;
+	uint32_t unique_hash;
 	char     devname[32];
 	char     id[80];
 	char     name[128];
@@ -1440,15 +1442,23 @@ int get_map_cancel()
 static char *get_map_name(int dev, int def)
 {
 	static char name[128];
-	if (def || is_menu()) sprintf(name, "input_%s%s_v3.map", input[dev].idstr, input[dev].mod ? "_m" : "");
-	else sprintf(name, "%s_input_%s%s_v3.map", user_io_get_core_name(), input[dev].idstr, input[dev].mod ? "_m" : "");
+	char id[32];
+	
+	if (cfg.unique_mapping) sprintfz(id, "%08x", input[dev].unique_hash);
+	else strcpyz(id, input[dev].idstr);
+
+	if (def || is_menu()) sprintf(name, "input_%s%s_v3.map", id, input[dev].mod ? "_m" : "");
+	else sprintf(name, "%s_input_%s%s_v3.map", user_io_get_core_name(), id, input[dev].mod ? "_m" : "");
 	return name;
 }
 
 static char *get_kbdmap_name(int dev)
 {
 	static char name[128];
-	sprintf(name, "kbd_%s.map", input[dev].idstr);
+	
+	if (cfg.unique_mapping) sprintfz(name, "kbd_%08x.map", input[dev].unique_hash);
+	else sprintfz(name, "kbd_%s.map", input[dev].idstr);
+	
 	return name;
 }
 
@@ -3385,6 +3395,12 @@ void mergedevs()
 									strcpy(input[i].id, id);
 									strcpy(input[i].sysfs, sysfs);
 									strcpy(input[i].mac, uniq);
+
+									int unique_hash = str_hash(input[i].id);
+									unique_hash = str_hash(input[i].mac, unique_hash);
+									unique_hash = str_hash(input[i].idstr, unique_hash);
+									input[i].unique_hash = unique_hash;
+
 									input[i].timeout = (strlen(uniq) && strstr(sysfs, "bluetooth")) ? (cfg.bt_auto_disconnect * 10) : 0;
 								}
 							}

str_util.cpp

@@ -31,4 +31,17 @@ char *strncpyz(char *dest, size_t dest_size, const char *src, size_t num)
 char *strcpyz(char *dest, size_t dest_size, const char *src)
 {
 	return strncpyz(dest, dest_size, src, dest_size - 1);
+}
+
+unsigned int str_hash(const char *s, unsigned int initial)
+{
+	unsigned int hash = initial;
+	int c;
+
+	while( c = *s++ )
+	{
+		hash = ((hash << 5) + hash) + c;
+	}
+
+	return hash;
 }

str_util.h

@@ -38,4 +38,6 @@ size_t sprintfz(char (&dest)[N], const char *fmt, ...)
 	return r;
 }
 
+unsigned int str_hash(const char *s, unsigned int initial = 5381);
+
 #endif // STR_UTIL_H