source code migrating from gitlab

004SendData/server-src/server.c

@@ -0,0 +1,161 @@
+#include <arpa/inet.h>
+#include <cjson/cJSON.h>
+#include <sqlite3.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#define PORT 9000
+#define BUFFER_SIZE 1024
+
+typedef struct ESPData {
+  double celsius;
+  double fahrenheit;
+  double humidity;
+} ESPData;
+
+int parseJSON(char buffer[BUFFER_SIZE], ESPData *espData);
+sqlite3 *initDB();
+int storeData(sqlite3 *db, ESPData espData);
+
+int main(int argc, char **argv) {
+
+  sqlite3 *db = initDB();
+  if (!db) {
+    exit(EXIT_FAILURE);
+  }
+
+  int serverSocket;
+  struct sockaddr_in serverAddr;
+
+  if ((serverSocket = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
+    perror("socket failed");
+    exit(EXIT_FAILURE);
+  }
+
+  serverAddr.sin_family = AF_INET;
+  serverAddr.sin_addr.s_addr = INADDR_ANY;
+  serverAddr.sin_port = htons(PORT);
+
+  if (bind(serverSocket, (struct sockaddr *)&serverAddr, sizeof serverAddr) <
+      0) {
+    perror("bind failed");
+    exit(EXIT_FAILURE);
+  }
+
+  if (listen(serverSocket, 5) < 0) {
+    perror("listen failed");
+    exit(EXIT_FAILURE);
+  }
+
+  printf("Server listening on port %d\n", PORT);
+  while (1) {
+
+    struct sockaddr_in clientAddr;
+    socklen_t clientAddr_len = sizeof clientAddr;
+    int *clientSocket = malloc(sizeof(int));
+
+    if ((*clientSocket = accept(serverSocket, (struct sockaddr *)&clientAddr,
+                                &clientAddr_len)) < 0) {
+      perror("accept failed");
+      continue;
+    }
+
+    printf("Connected\n");
+
+    // Receive from Client
+    char buf[BUFFER_SIZE];
+    int bytes = recv(*clientSocket, buf, sizeof buf, 0);
+    if (bytes <= 0) {
+      perror("failed to recv from client");
+      continue;
+    }
+    printf("raw data: %s\n", buf);
+
+    // Parse JSON
+    ESPData espData;
+    if (parseJSON(buf, &espData) == 0) {
+      printf("Fahrenheit: %.2f, Celsius: %.2f, Humidity: %.2f\n",
+             espData.fahrenheit, espData.celsius, espData.humidity);
+
+      storeData(db, espData);
+    }
+
+    close(*clientSocket);
+    printf("disconnected client.\n");
+  }
+
+  close(serverSocket);
+  return 0;
+}
+
+int parseJSON(char buffer[BUFFER_SIZE], ESPData *espData) {
+
+  // char *data = strstr(buffer, "\r\n\r\n");
+  // if (data) {
+  //   data += 4;
+  // } else {
+  //   return -1;
+  // }
+
+  const cJSON *fahr;
+  const cJSON *cel;
+  const cJSON *hum;
+  cJSON *jsonData = cJSON_Parse(buffer);
+
+  fahr = cJSON_GetObjectItem(jsonData, "fahrenheit");
+  if (!fahr || !cJSON_IsNumber(fahr)) {
+    printf("Error: failed to parse fahrenheit\n");
+    cJSON_Delete(jsonData);
+    return -1;
+  }
+
+  cel = cJSON_GetObjectItem(jsonData, "celsius");
+  if (!cel || !cJSON_IsNumber(cel)) {
+    printf("Error: failed to parse celsius\n");
+    cJSON_Delete(jsonData);
+    return -1;
+  }
+
+  hum = cJSON_GetObjectItem(jsonData, "humidity");
+  if (!hum || !cJSON_IsNumber(hum)) {
+    printf("Error: failed to parse humidity\n");
+    cJSON_Delete(jsonData);
+    return -1;
+  }
+
+  espData->fahrenheit = fahr->valuedouble;
+  espData->celsius = cel->valuedouble;
+  espData->humidity = hum->valuedouble;
+
+  cJSON_Delete(jsonData);
+  return 0;
+}
+
+sqlite3 *initDB() {
+  sqlite3 *db = NULL;
+  int res = sqlite3_open("stats.db", &db);
+  if (res != SQLITE_OK) {
+    fprintf(stderr, "Failed to open the db: %s", sqlite3_errmsg(db));
+  }
+
+  return db;
+}
+int storeData(sqlite3 *db, ESPData espData) {
+
+  char sql[256];
+  sprintf(sql,
+          "insert into Stats(Id, Fahrenheit, Celsius, Humidity) values(NULL, "
+          "'%f', '%f', '%f');",
+          espData.fahrenheit, espData.celsius, espData.humidity);
+
+  char *errMsg;
+  int res = sqlite3_exec(db, sql, 0, 0, &errMsg);
+  if (res != SQLITE_OK) {
+    fprintf(stderr, "Could not insert into DB: %s", errMsg);
+    sqlite3_free(errMsg);
+    return -1;
+  }
+  return 0;
+}