Adafruit_GPS/extras/tests/parse_str/parse_str.ino

// String-copy and sentence bounds regression. Runs without a GPS receiver.

// Test the private field helper without changing the library's public API.
#include <Arduino.h>
#include <SPI.h>
#include <Wire.h>
#define private public
#include <Adafruit_GPS.h>
#undef private

bool checkField(const char *value, uint8_t capacity, const char *expected);

Adafruit_GPS GPS;
bool testsPassed = false;

void setup() {
  Serial.begin(115200);
  // Wait briefly for the Serial Monitor on native USB boards.
  while (!Serial && millis() < 5000) {
    delay(10);
  }
  delay(250);
  Serial.println("Adafruit GPS text field bounds regression");

  char valid[] =
      "$GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47";
  Serial.println(valid);
  if (!GPS.parse(valid)) {
    Serial.println("FAIL: valid GGA sentence did not parse");
    return;
  }
  Serial.println("PASS: valid GGA sentence parsed");

  // Valid checksum, but the unknown identifier exceeds the 19-character
  // destination. Before the fix, its terminator overwrites lastSource[0].
  char invalid[] = "$GPXXXXXXXXXXXXXXXXXXXX*17";
  Serial.println(invalid);
  if (GPS.parse(invalid)) {
    Serial.println("FAIL: unknown sentence was accepted");
    return;
  }
  Serial.println("PASS: unknown sentence rejected");

  // Rejection alone passed before the fix too. The last valid sentence's
  // identity must also survive, proving that the rejected input stayed in bounds.
  if (strcmp(GPS.lastSource, "GP") != 0 ||
      strcmp(GPS.lastSentence, "GGA") != 0) {
    Serial.println("FAIL: rejected sentence corrupted the previous result");
    return;
  }
  Serial.println("PASS: previous result preserved");

  // Each destination starts with nonzero bytes so missing terminators fail.
  if (!checkField("abc,tail", 8, "abc") ||
      !checkField("abc*00", 8, "abc") ||
      !checkField("abc", 8, "abc") ||
      !checkField("abcdef,tail", 4, "abc") ||
      !checkField("abcdef*00", 4, "abc") ||
      !checkField("abcdef", 4, "abc") ||
      !checkField("abc", 1, "") ||
      !checkField("", 8, "")) {
    return;
  }
  testsPassed = true;
}

void loop() {
  if (testsPassed) {
    Serial.println("PASS: string-copy regression");
  } else {
    Serial.println("FAIL: string-copy regression");
  }
  delay(2000);
}

bool checkField(const char *value, uint8_t capacity, const char *expected) {
  char input[24];
  char result[9];
  strcpy(input, value);
  memset(result, '?', sizeof(result));
  if (GPS.parseStr(result, input, capacity) != result ||
      memcmp(result, expected, strlen(expected) + 1) != 0 ||
      result[capacity] != '?') {
    Serial.println("FAIL: copied field or destination bounds");
    return false;
  }
  Serial.print("PASS: copied field ");
  Serial.println(value);
  return true;
}