From 7a8ee567b6d18bc29c1605655dbffb7bdc2cbed6 Mon Sep 17 00:00:00 2001
From: Our Air Quality <info@ourairquality.org>
Date: Sun, 17 Jun 2018 20:08:58 +1000
Subject: [PATCH] libmain: add a compile option to avoid saving wifi params to
 flash

Add source code for sdk_wifi_param_save_protect() and a compile time,
WIFI_PARAM_SAVE, option to skip writing the wifi state to flash. This
avoids wear on the flash and does not appear to be necessary when the
app initializes the state anyway.

Define WIFI_PARAM_SAVE to 0 for the wificfg example.
---
 examples/wificfg/Makefile             |  9 +++--
 open_esplibs/libmain/user_interface.c | 50 +++++++++++++++++++++++++++
 2 files changed, 56 insertions(+), 3 deletions(-)

diff --git a/examples/wificfg/Makefile b/examples/wificfg/Makefile
index 586b087..51b177f 100644
--- a/examples/wificfg/Makefile
+++ b/examples/wificfg/Makefile
@@ -3,10 +3,13 @@ PROGRAM=wificfg
 EXTRA_COMPONENTS=extras/dhcpserver extras/wificfg
 
 # For the mDNS responder included under extras:
-# EXTRA_COMPONENTS+=extras/mdnsresponder
-# EXTRA_CFLAGS=-DEXTRAS_MDNS_RESPONDER
+# EXTRA_COMPONENTS += extras/mdnsresponder
+# EXTRA_CFLAGS += -DEXTRAS_MDNS_RESPONDER
 
 # For the mDNS responder included with lwip:
-EXTRA_CFLAGS=-DLWIP_MDNS_RESPONDER=1 -DLWIP_NUM_NETIF_CLIENT_DATA=1 -DLWIP_NETIF_EXT_STATUS_CALLBACK=1
+EXTRA_CFLAGS += -DLWIP_MDNS_RESPONDER=1 -DLWIP_NUM_NETIF_CLIENT_DATA=1 -DLWIP_NETIF_EXT_STATUS_CALLBACK=1
+
+# Avoid writing the wifi state to flash when using wificfg.
+EXTRA_CFLAGS += -DWIFI_PARAM_SAVE=0
 
 include ../../common.mk
diff --git a/open_esplibs/libmain/user_interface.c b/open_esplibs/libmain/user_interface.c
index e81f175..cc0ffbe 100644
--- a/open_esplibs/libmain/user_interface.c
+++ b/open_esplibs/libmain/user_interface.c
@@ -576,6 +576,56 @@ enum sdk_dhcp_status sdk_wifi_station_dhcpc_status(void) {
     return sdk_dhcpc_flag;
 }
 
+
+#ifndef WIFI_PARAM_SAVE
+#define WIFI_PARAM_SAVE 1
+#endif
+
+#if WIFI_PARAM_SAVE
+static void wifi_save_protect(uint32_t sector, uint32_t sector_size, uint32_t *arg2, size_t size) {
+    uint32_t *buffer = malloc(size);
+    uint32_t offset = sector * sector_size;
+
+    do  {
+        sdk_spi_flash_erase_sector(sector);
+        sdk_spi_flash_write(offset, arg2, size);
+        sdk_spi_flash_read(offset, buffer, size);
+        if (memcmp(buffer, arg2, size) == 0) {
+            break;
+        }
+        printf("[W]sec %d error\n", sector);
+    } while (1);
+
+    free(buffer);
+}
+#endif
+
+void sdk_wifi_param_save_protect(struct sdk_g_ic_saved_st *params) {
+#if WIFI_PARAM_SAVE
+    uint32_t sector_size = sdk_flashchip.sector_size;
+    uint32_t sectors = sdk_flashchip.chip_size / sector_size;
+
+    uint32_t dir_sector = sectors - 1;
+    struct param_dir_st dir;
+    sdk_spi_flash_read(dir_sector * sector_size, (uint32_t *)&dir, sizeof(dir));
+    uint8_t current_sector = dir.current_sector ? 1 : 0;
+    dir.current_sector = current_sector;
+
+    uint32_t param_sector_start = sectors - 3;
+    wifi_save_protect(param_sector_start + current_sector, sector_size,
+                      (uint32_t *)params, sizeof(struct sdk_g_ic_saved_st));
+
+    dir.cksum_magic = 0x55AA55AA;
+    uint32_t save_count = dir.save_count + 1;
+    dir.save_count = (save_count) ? save_count : 1;
+    dir.cksum_len[current_sector] = sizeof(dir);
+    uint32_t checksum = sdk_system_get_checksum((uint8_t *)params, sizeof(dir));
+    dir.cksum_value[current_sector] = checksum;
+    wifi_save_protect(dir_sector, sector_size, (uint32_t *)&dir, sizeof(dir));
+#endif
+}
+
+
 uint8_t sdk_wifi_station_get_connect_status() {
     if (sdk_wifi_get_opmode() == 2) // ESPCONN_AP
         return 0xff;