Comms refactor (prerequisite of libproxmark work) (#371)

* Refactor the comms code only from PR#346, without comms_globals.h.
* OSX: Add note for example serial port

client/flash.c

@@ -13,6 +13,7 @@
 #include <stdlib.h>
 #include <inttypes.h>
 #include <unistd.h>
+
 #include "proxmark3.h"
 #include "util.h"
 #include "util_posix.h"
@@ -20,11 +21,7 @@
 #include "elf.h"
 #include "proxendian.h"
 #include "usb_cmd.h"
-
-void SendCommand(UsbCommand* txcmd);
-void ReceiveCommand(UsbCommand* rxcmd);
-void CloseProxmark();
-int OpenProxmark(size_t i);
+#include "comms.h"
 
 // FIXME: what the fuckity fuck
 unsigned int current_command = CMD_UNKNOWN;
@@ -44,6 +41,32 @@ static const uint8_t elf_ident[] = {
 	EV_CURRENT
 };
 
+void CloseProxmark(receiver_arg* conn, char* serial_port_name) {
+	pthread_mutex_lock(&conn->recv_lock);
+
+	// Block the port from being used by anything
+	serial_port* my_port = GetSerialPort();
+	SetSerialPort(NULL);
+
+	// Then close the port.
+	uart_close(my_port);
+	pthread_mutex_unlock(&conn->recv_lock);
+
+	// Fix for linux, it seems that it is extremely slow to release the serial port file descriptor /dev/*
+	unlink(serial_port_name);
+}
+
+bool OpenProxmark(char* serial_port_name) {
+	serial_port *new_port = uart_open(serial_port_name);
+	if (new_port == INVALID_SERIAL_PORT || new_port == CLAIMED_SERIAL_PORT) {
+		//poll once a second
+		return false;
+	}
+	
+	SetSerialPort(new_port);
+	return true;
+}
+
 // Turn PHDRs into flasher segments, checking for PHDR sanity and merging adjacent
 // unaligned segments if needed
 static int build_segs_from_phdrs(flash_file_t *ctx, FILE *fd, Elf32_Phdr *phdrs, int num_phdrs)
@@ -278,9 +301,12 @@ static int get_proxmark_state(uint32_t *state)
 {
 	UsbCommand c;
 	c.cmd = CMD_DEVICE_INFO;
-  SendCommand(&c);
+	SendCommand(&c);
 	UsbCommand resp;
-	ReceiveCommand(&resp);
+	while (!WaitForResponse(CMD_ANY, &resp)) {
+		// Keep waiting for a response
+		msleep(100);
+	}
 
 	// Three outcomes:
 	// 1. The old bootrom code will ignore CMD_DEVICE_INFO, but respond with an ACK
@@ -307,7 +333,7 @@ static int get_proxmark_state(uint32_t *state)
 }
 
 // Enter the bootloader to be able to start flashing
-static int enter_bootloader(char *serial_port_name)
+static int enter_bootloader(receiver_arg* conn, char *serial_port_name)
 {
 	uint32_t state;
 
@@ -338,16 +364,17 @@ static int enter_bootloader(char *serial_port_name)
 			SendCommand(&c);
 			fprintf(stderr,"Press and hold down button NOW if your bootloader requires it.\n");
 		}
-    msleep(100);
-		CloseProxmark();
+		
+		msleep(100);
+		CloseProxmark(conn, serial_port_name);
 
 		fprintf(stderr,"Waiting for Proxmark to reappear on %s",serial_port_name);
-    do {
+		do {
 			sleep(1);
 			fprintf(stderr, ".");
-		} while (!OpenProxmark(0));
+		} while (!OpenProxmark(serial_port_name));
+		
 		fprintf(stderr," Found.\n");
-
 		return 0;
 	}
 
@@ -355,23 +382,25 @@ static int enter_bootloader(char *serial_port_name)
 	return -1;
 }
 
-static int wait_for_ack(void)
+static int wait_for_ack()
 {
-  UsbCommand ack;
-	ReceiveCommand(&ack);
-	if (ack.cmd != CMD_ACK) {
-		printf("Error: Unexpected reply 0x%04" PRIx64 " (expected ACK)\n", ack.cmd);
+	UsbCommand resp;
+	while (!WaitForResponse(CMD_ANY, &resp)) {
+		msleep(100);
+	}
+	if (resp.cmd != CMD_ACK) {
+		printf("Error: Unexpected reply 0x%04" PRIx64 " (expected ACK)\n", resp.cmd);
 		return -1;
 	}
 	return 0;
 }
 
 // Go into flashing mode
-int flash_start_flashing(int enable_bl_writes,char *serial_port_name)
+int flash_start_flashing(receiver_arg* conn, int enable_bl_writes,char *serial_port_name)
 {
 	uint32_t state;
 
-	if (enter_bootloader(serial_port_name) < 0)
+	if (enter_bootloader(conn, serial_port_name) < 0)
 		return -1;
 
 	if (get_proxmark_state(&state) < 0)
@@ -470,9 +499,9 @@ void flash_free(flash_file_t *ctx)
 }
 
 // just reset the unit
-int flash_stop_flashing(void) {
+int flash_stop_flashing() {
 	UsbCommand c = {CMD_HARDWARE_RESET};
-  SendCommand(&c);
-  msleep(100);
-  return 0;
+	SendCommand(&c);
+	msleep(100);
+	return 0;
 }