Finished Language Generation Tool

src/dawntools/util/File.cpp

@@ -126,6 +126,46 @@ bool_t File::readString(std::string *out) {
   return true;
 }
 
+size_t File::readAhead(char *buffer, size_t max, char needle) {
+  assertNotNull(buffer);
+  assertTrue(max > 0);
+
+  if(!this->isOpen()) {
+    if(!this->open(FILE_MODE_READ)) return 0;
+  }
+  assertTrue(this->mode == FILE_MODE_READ);
+
+  // Buffer
+  size_t pos = ftell(this->file);
+  size_t amountLeftToRead = mathMin<size_t>(max, this->length - pos);
+  char temporary[FILE_BUFFER_SIZE];
+  size_t n = 0;
+  
+  while(amountLeftToRead > 0) {
+    size_t toRead = mathMin<size_t>(amountLeftToRead, FILE_BUFFER_SIZE);
+    amountLeftToRead -= toRead;
+    // Read bytes
+    size_t read = fread(temporary, sizeof(char), toRead, this->file);
+
+    // Read error?
+    if(toRead != read) return 0;
+
+    // Did we read the needle?
+    size_t i = 0;
+    while(i < read) {
+      char c = temporary[i++];
+      if(c == needle) {
+        return n;
+      } else {
+        buffer[n++] = c;
+      }
+    }
+  }
+
+  // Needle was not found.
+  return -1;
+}
+
 bool_t File::writeString(std::string in) {
   if(!this->isOpen()) {
     if(!this->open(FILE_MODE_WRITE)) return false;
@@ -143,6 +183,11 @@ bool_t File::writeRaw(char *data, size_t len) {
   return true;
 }
 
+void File::setPosition(size_t n) {
+  fseek(this->file, 0, SEEK_SET);
+  fseek(this->file, n, SEEK_CUR);
+}
+
 File::~File() {
   if(this->file != nullptr) this->close();
 }

src/dawntools/util/File.hpp

@@ -33,14 +33,14 @@ namespace Dawn {
   class File {
     private:
       enum FileMode mode;
-      size_t length;
 
     public:
-      FILE *file = nullptr;
       static std::string normalizeSlashes(std::string str);
       static void mkdirp(std::string path);
 
       std::string filename;
+      size_t length;
+      FILE *file = nullptr;
 
       /**
        * Constructs a new File interface class.
@@ -95,6 +95,20 @@ namespace Dawn {
        */
       bool_t readString(std::string *out);
 
+      /**
+       * Reads ahead from the current position to a specific needle (character).
+       * 
+       * @param buffer Buffer to output read chars to.
+       * @param max Max length of the buffer / amount of chars to read ahead.
+       * @param needle The character (needle) to look for.
+       * @return Amount of chars read, or <= 0 on error.
+       */
+      size_t readAhead(
+        char *buffer,
+        size_t max,
+        char needle
+      );
+
       /**
        * Writes the entire contents of a string to a file.
        * 
@@ -111,6 +125,8 @@ namespace Dawn {
        */
       bool_t writeRaw(char *data, size_t );
 
+      void setPosition(size_t pos);
+
       ~File();
   };
 }