thodg/cgminer

diff --git a/API-README b/API-README
index 14f8b53..d8a5dec 100644
--- a/API-README
+++ b/API-README
@@ -347,6 +347,18 @@ The list of requests - a (*) means it requires privileged access - and replies a
                               The current options are:
                                MMQ opt=clock val=160 to 230 (and a multiple of 2)
 
+ zero|Which,true/false (*)
+               none           There is no reply section just the STATUS section
+                              stating that the zero, and optional summary, was done
+                              If Which='all', all normal cgminer and API statistics
+                              will be zeroed other than the numbers displayed by the
+                              usbstats and stats commands
+                              If Which='bestshare', only the 'Best Share' values
+                              are zeroed for each pool and the global 'Best Share'
+                              The true/false option determines if a full summary is
+                              shown on the cgminer display like is normally displayed
+                              on exit.
+
 When you enable, disable or restart a GPU or PGA, you will also get Thread messages
 in the cgminer status window
 
@@ -402,6 +414,9 @@ Feature Changelog for external applications using the API:
 
 API V1.24
 
+Added API commands:
+ 'zero'
+
 Modified API commands:
  'pools' - add 'Best Share'
 
diff --git a/api.c b/api.c
index bfd8370..faad39a 100644
--- a/api.c
+++ b/api.c
@@ -387,6 +387,11 @@ static const char *JSON_PARAMETER = "parameter";
 #define MSG_PGASETERR 93
 #endif
 
+#define MSG_ZERMIS 94
+#define MSG_ZERINV 95
+#define MSG_ZERSUM 96
+#define MSG_ZERNOSUM 97
+
 enum code_severity {
 	SEVERITY_ERR,
 	SEVERITY_WARN,
@@ -559,6 +564,10 @@ struct CODES {
  { SEVERITY_SUCC,  MSG_PGASETOK, PARAM_BOTH,	"PGA %d set OK" },
  { SEVERITY_ERR,   MSG_PGASETERR, PARAM_BOTH,	"PGA %d set failed: %s" },
 #endif
+ { SEVERITY_ERR,   MSG_ZERMIS,	PARAM_NONE,	"Missing zero parameters" },
+ { SEVERITY_ERR,   MSG_ZERINV,	PARAM_STR,	"Invalid zero parameter '%s'" },
+ { SEVERITY_SUCC,  MSG_ZERSUM,	PARAM_STR,	"Zeroed %s stats with summary" },
+ { SEVERITY_SUCC,  MSG_ZERNOSUM, PARAM_STR,	"Zeroed %s stats without summary" },
  { SEVERITY_FAIL, 0, 0, NULL }
 };
 
@@ -3212,6 +3221,54 @@ static void pgaset(struct io_data *io_data, __maybe_unused SOCKETTYPE c, __maybe
 }
 #endif
 
+static void dozero(struct io_data *io_data, __maybe_unused SOCKETTYPE c, char *param, bool isjson, __maybe_unused char group)
+{
+	if (param == NULL || *param == '\0') {
+		message(io_data, MSG_ZERMIS, 0, NULL, isjson);
+		return;
+	}
+
+	char *sum = strchr(param, ',');
+	if (sum)
+		*(sum++) = '\0';
+	if (!sum || !*sum) {
+		message(io_data, MSG_MISBOOL, 0, NULL, isjson);
+		return;
+	}
+
+	bool all = false;
+	bool bs = false;
+	if (strcasecmp(param, "all") == 0)
+		all = true;
+	else if (strcasecmp(param, "bestshare") == 0)
+		bs = true;
+
+	if (all == false && bs == false) {
+		message(io_data, MSG_ZERINV, 0, param, isjson);
+		return;
+	}
+
+	*sum = tolower(*sum);
+	if (*sum != 't' && *sum != 'f') {
+		message(io_data, MSG_INVBOOL, 0, NULL, isjson);
+		return;
+	}
+
+	bool dosum = (*sum == 't');
+	if (dosum)
+		print_summary();
+
+	if (all)
+		zero_stats();
+	if (bs)
+		zero_bestshare();
+
+	if (dosum)
+		message(io_data, MSG_ZERSUM, 0, all ? "All" : "BestShare", isjson);
+	else
+		message(io_data, MSG_ZERNOSUM, 0, all ? "All" : "BestShare", isjson);
+}
+
 static void checkcommand(struct io_data *io_data, __maybe_unused SOCKETTYPE c, char *param, bool isjson, char group);
 
 struct CMDS {
@@ -3271,6 +3328,7 @@ struct CMDS {
 #ifdef HAVE_AN_FPGA
 	{ "pgaset",		pgaset,		true },
 #endif
+	{ "zero",		dozero,		true },
 	{ NULL,			NULL,		false }
 };
 
diff --git a/cgminer.c b/cgminer.c
index 1bc57e9..c42703f 100644
--- a/cgminer.c
+++ b/cgminer.c
@@ -2732,8 +2732,6 @@ static void disable_curses(void)
 }
 #endif
 
-static void print_summary(void);
-
 static void __kill_work(void)
 {
 	struct thr_info *thr;
@@ -3915,6 +3913,20 @@ void write_config(FILE *fcfg)
 	json_escape_free();
 }
 
+void zero_bestshare(void)
+{
+	int i;
+
+	best_diff = 0;
+	memset(best_share, 0, 8);
+	suffix_string(best_diff, best_share, 0);
+
+	for (i = 0; i < total_pools; i++) {
+		struct pool *pool = pools[i];
+		pool->best_diff = 0;
+	}
+}
+
 void zero_stats(void)
 {
 	int i;
@@ -3931,10 +3943,7 @@ void zero_stats(void)
 	total_go = 0;
 	total_ro = 0;
 	total_secs = 1.0;
-	best_diff = 0;
 	total_diff1 = 0;
-	memset(best_share, 0, 8);
-	suffix_string(best_diff, best_share, 0);
 	found_blocks = 0;
 	total_diff_accepted = 0;
 	total_diff_rejected = 0;
@@ -3956,9 +3965,10 @@ void zero_stats(void)
 		pool->diff_rejected = 0;
 		pool->diff_stale = 0;
 		pool->last_share_diff = 0;
-		pool->best_diff = 0;
 	}
 
+	zero_bestshare();
+
 	mutex_lock(&hash_lock);
 	for (i = 0; i < total_devices; ++i) {
 		struct cgpu_info *cgpu = devices[i];
@@ -5961,7 +5971,7 @@ static void log_print_status(struct cgpu_info *cgpu)
 	applog(LOG_WARNING, "%s", logline);
 }
 
-static void print_summary(void)
+void print_summary(void)
 {
 	struct timeval diff;
 	int hours, mins, secs, i;
diff --git a/miner.h b/miner.h
index b89d072..1992bd5 100644
--- a/miner.h
+++ b/miner.h
@@ -759,6 +759,7 @@ extern void api(int thr_id);
 extern struct pool *current_pool(void);
 extern int enabled_pools;
 extern bool detect_stratum(struct pool *pool, char *url);
+extern void print_summary(void);
 extern struct pool *add_pool(void);
 extern void add_pool_details(struct pool *pool, bool live, char *url, char *user, char *pass);
 
@@ -1077,6 +1078,8 @@ extern void kill_work(void);
 extern void switch_pools(struct pool *selected);
 extern void remove_pool(struct pool *pool);
 extern void write_config(FILE *fcfg);
+extern void zero_bestshare(void);
+extern void zero_stats(void);
 extern void default_save_file(char *filename);
 extern bool log_curses_only(int prio, const char *f, va_list ap);
 extern void clear_logwin(void);