add wifi_cfg NVS credential storage

main/wifi_cfg.c

@@ -0,0 +1,118 @@
+#include "wifi_cfg.h"
+#include <string.h>
+#include <stdio.h>
+#include "nvs_flash.h"
+#include "nvs.h"
+
+#define NVS_NS       "wifi_prov"
+#define KEY_STA_SSID "sta_ssid"
+#define KEY_STA_PASS "sta_pass"
+#define KEY_AP_SSID  "ap_ssid"
+#define KEY_AP_PASS  "ap_pass"
+
+#define DEFAULT_AP_SSID "EIS4"
+#define DEFAULT_AP_PASS "eis4data"
+
+static char sta_ssid[WIFI_CFG_SSID_MAX];
+static char sta_pass[WIFI_CFG_PASS_MAX];
+static char ap_ssid[WIFI_CFG_SSID_MAX];
+static char ap_pass[WIFI_CFG_PASS_MAX];
+
+esp_err_t wifi_cfg_init(void)
+{
+    memset(sta_ssid, 0, sizeof(sta_ssid));
+    memset(sta_pass, 0, sizeof(sta_pass));
+    strncpy(ap_ssid, DEFAULT_AP_SSID, sizeof(ap_ssid) - 1);
+    strncpy(ap_pass, DEFAULT_AP_PASS, sizeof(ap_pass) - 1);
+
+    nvs_handle_t h;
+    esp_err_t err = nvs_open(NVS_NS, NVS_READONLY, &h);
+    if (err == ESP_ERR_NVS_NOT_FOUND)
+        return ESP_OK;
+    if (err != ESP_OK)
+        return err;
+
+    size_t len;
+
+    len = sizeof(sta_ssid);
+    nvs_get_str(h, KEY_STA_SSID, sta_ssid, &len);
+    len = sizeof(sta_pass);
+    nvs_get_str(h, KEY_STA_PASS, sta_pass, &len);
+
+    len = sizeof(ap_ssid);
+    if (nvs_get_str(h, KEY_AP_SSID, ap_ssid, &len) != ESP_OK) {
+        strncpy(ap_ssid, DEFAULT_AP_SSID, sizeof(ap_ssid) - 1);
+    }
+    len = sizeof(ap_pass);
+    if (nvs_get_str(h, KEY_AP_PASS, ap_pass, &len) != ESP_OK) {
+        strncpy(ap_pass, DEFAULT_AP_PASS, sizeof(ap_pass) - 1);
+    }
+
+    nvs_close(h);
+
+    if (sta_ssid[0])
+        printf("WiFi cfg: STA \"%s\"\n", sta_ssid);
+    printf("WiFi cfg: AP \"%s\"\n", ap_ssid);
+    return ESP_OK;
+}
+
+bool wifi_cfg_has_sta(void)
+{
+    return sta_ssid[0] != '\0';
+}
+
+esp_err_t wifi_cfg_get_sta(char *ssid, size_t ssid_sz, char *pass, size_t pass_sz)
+{
+    if (!sta_ssid[0])
+        return ESP_ERR_NOT_FOUND;
+    strncpy(ssid, sta_ssid, ssid_sz - 1);
+    ssid[ssid_sz - 1] = '\0';
+    strncpy(pass, sta_pass, pass_sz - 1);
+    pass[pass_sz - 1] = '\0';
+    return ESP_OK;
+}
+
+esp_err_t wifi_cfg_set_sta(const char *ssid, const char *pass)
+{
+    nvs_handle_t h;
+    esp_err_t err = nvs_open(NVS_NS, NVS_READWRITE, &h);
+    if (err != ESP_OK) return err;
+
+    nvs_set_str(h, KEY_STA_SSID, ssid);
+    nvs_set_str(h, KEY_STA_PASS, pass);
+    nvs_commit(h);
+    nvs_close(h);
+
+    strncpy(sta_ssid, ssid, sizeof(sta_ssid) - 1);
+    sta_ssid[sizeof(sta_ssid) - 1] = '\0';
+    strncpy(sta_pass, pass, sizeof(sta_pass) - 1);
+    sta_pass[sizeof(sta_pass) - 1] = '\0';
+    return ESP_OK;
+}
+
+esp_err_t wifi_cfg_get_ap(char *ssid, size_t ssid_sz, char *pass, size_t pass_sz)
+{
+    strncpy(ssid, ap_ssid, ssid_sz - 1);
+    ssid[ssid_sz - 1] = '\0';
+    strncpy(pass, ap_pass, pass_sz - 1);
+    pass[pass_sz - 1] = '\0';
+    return ESP_OK;
+}
+
+esp_err_t wifi_cfg_set_ap(const char *ssid, const char *pass)
+{
+    nvs_handle_t h;
+    esp_err_t err = nvs_open(NVS_NS, NVS_READWRITE, &h);
+    if (err != ESP_OK) return err;
+
+    nvs_set_str(h, KEY_AP_SSID, ssid);
+    nvs_set_str(h, KEY_AP_PASS, pass);
+    nvs_commit(h);
+    nvs_close(h);
+
+    strncpy(ap_ssid, ssid, sizeof(ap_ssid) - 1);
+    ap_ssid[sizeof(ap_ssid) - 1] = '\0';
+    strncpy(ap_pass, pass, sizeof(ap_pass) - 1);
+    ap_pass[sizeof(ap_pass) - 1] = '\0';
+    return ESP_OK;
+}

main/wifi_cfg.h

@@ -0,0 +1,18 @@
+#ifndef WIFI_CFG_H
+#define WIFI_CFG_H
+
+#include <stdbool.h>
+#include <stddef.h>
+#include "esp_err.h"
+
+#define WIFI_CFG_SSID_MAX 33
+#define WIFI_CFG_PASS_MAX 65
+
+esp_err_t wifi_cfg_init(void);
+bool      wifi_cfg_has_sta(void);
+esp_err_t wifi_cfg_get_sta(char *ssid, size_t ssid_sz, char *pass, size_t pass_sz);
+esp_err_t wifi_cfg_set_sta(const char *ssid, const char *pass);
+esp_err_t wifi_cfg_get_ap(char *ssid, size_t ssid_sz, char *pass, size_t pass_sz);
+esp_err_t wifi_cfg_set_ap(const char *ssid, const char *pass);
+
+#endif