sdcard.cpp

#include "GrowduinoFirmware.h"

#include <SD.h>
#include <aJSON.h>

const int chipSelect = 4;

bool sdcard_init() {
  bool ret;
  pinMode(53, OUTPUT);
  ret = SD.begin(chipSelect);
  return ret;
}

bool file_exists(const char * dirname) {
  // check if directory (or full filename) exists
  return file_exists(dirname, NULL);
}

bool file_exists(const char * dirname, const char * filename) {
  char full_file_name[70];
  strlcpy(full_file_name, dirname, 55);
  if (filename == NULL) {
    return SD.exists(full_file_name);
  } else {
    if (strlen(dirname) > 50) {
      //we dont do that deep dirs
      return false;
    }
    strlcpy(full_file_name, dirname, 55);
    strlcat(full_file_name, "/", 70);
    strlcat(full_file_name, filename, 70);
    return SD.exists(full_file_name);

  }
}

int file_for_write(const char * dirname, const char * filename, File * dataFile) {
  char filepath[128];

  if (strlen(dirname) > 50) {
    //we dont do that deep dirs
    return -1;
  }

  strlcpy(filepath, dirname, 55);
  if (!file_exists(filepath) && dirname[0] == '/') {
#ifdef DEBUG_SDCARD
    SERIAL.print(F("Creating directory: "));
#endif
    SD.mkdir(filepath);
  }
  strlcat(filepath, "/", 60);
  strlcat(filepath, filename, 60);

#ifdef DEBUG_SDCARD
  SERIAL.print(F("Writing file "));
  SERIAL.println(filepath);
#endif

  if (file_exists(filepath)) {
    SD.remove(filepath);
  }

  digitalWrite(13, 1);

#ifdef DEBUG_SDCARD
  SERIAL.print(F("."));
#endif

  *dataFile = SD.open(filepath, FILE_WRITE);
  return 1;
}

void file_passthru(const char * dirname, const char * filename, Stream * input) {
  File dataFile;
  char buf[128];
  int res = file_for_write(dirname, filename, &dataFile);

#ifdef WATCHDOG
  wdt_reset();
#endif
#ifdef DEBUG_SDCARD
  SERIAL.println(F("file_passthru"));
#endif
  digitalWrite(13, 1);
  if (res != -1) {
    SERIAL.print(F("saving data to disk"));
    int remain = 0;
    while ((remain = input->available())) {
      remain = min(remain, 127);
      for (int i = 0; i < remain; i++) {
        buf[i] = (char) input->read();
      }
      buf[remain] = 0;
      dataFile.write(buf);
      SERIAL.print(F("."));
    };
    dataFile.close();

  } else {
    SERIAL.print(F("Failed to open "));
    SERIAL.println(filename);
  }
#ifdef DEBUG_SDCARD
  SERIAL.println(F(";"));
#endif
  digitalWrite(13, 0);
}


void file_write(const char * dirname, const char * filename, aJsonObject * data) {
  File dataFile;
  int res = file_for_write(dirname, filename, &dataFile);
#ifdef DEBUG_SDCARD
  SERIAL.println(F("file_write"));
#endif
  if (res != -1) {
    aJsonStream sd_stream(&dataFile);
    aJson.print(data, &sd_stream);
#ifdef DEBUG_SDCARD
    SERIAL.print(F("."));
#endif
    dataFile.close();
#ifdef DEBUG_SDCARD
    SERIAL.print(F("."));
#endif
  } else {
    SERIAL.print(F("Failed to open "));
    SERIAL.println(filename);
  }
#ifdef DEBUG_SDCARD
  SERIAL.println(F(";"));
#endif
  digitalWrite(13, 0);
}

aJsonObject * file_read(const char * dirname, const char * filename) {
  char filepath[60];

  if (strlen(dirname) > 50 || strstr(dirname, "..") != NULL) {
    //we dont do that deep dirs, we dont support taversal up
    return NULL;
  }

  strcpy(filepath, dirname);
  strncat(filepath, "/", sizeof(filepath) - 2);
  strncat(filepath, filename, sizeof(filepath) - strlen(filename) - 1);
  //strcat(filepath, "/");
  //strcat(filepath, filename);

  SERIAL.print(F("opening file "));
  SERIAL.println(filepath);

  if (!SD.exists(filepath)) {
    SERIAL.println(F("File does not exist"));
    return NULL;
  }
  File dataFile = SD.open(filepath, FILE_READ);
  if (dataFile) {
    aJsonStream sd_stream(&dataFile);
    aJsonObject * data = aJson.parse(&sd_stream);
    dataFile.close();
    return data;
  } else {
    SERIAL.println(F("File read failure"));
    return NULL;
  }

}