Bootstrapping

compiler.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(int argc, char *argv[]) {
  // We need 4 arguments "program source -o binary"
  if (argc < 4) {
    printf("Insufficient arguments\n");
    return 1;
  }

  char * sourceFilename = argv[1];
  char * destFilename = argv[3];

  FILE * inputFile = fopen(sourceFilename, "r");

  if(inputFile == NULL) {
    printf("File does not exist");
    return 1;
  }


  // Get source file size
  fseek(inputFile, 0 , SEEK_END);
  int sourceFileSize = ftell(inputFile);
  rewind(inputFile);

  // Read source file into buffer with one extra byte to accomodate '\0'
  int actualBuffSizeRequired = sourceFileSize + 1;
  char * buffer = (char *) malloc(actualBuffSizeRequired);
  buffer[sourceFileSize] = '\0';
  int read = fread(buffer, sizeof(char), sourceFileSize, inputFile);
  fclose(inputFile);

  /* We pass the source code to GCC as the backend compiler */
  char compileCommand[500];

  // Generate compile command, tell GCC to assume C language and get source code via stdin
  snprintf(compileCommand, 500, "gcc -o %s -xc -", destFilename);

  FILE * gccStdin;
  gccStdin = popen(compileCommand, "w");

  // Pass source code to GCC via stdin
  fwrite(buffer, sizeof(char), sourceFileSize, gccStdin);

  // Print actual source code used in compilation for reference
  printf("%s\n", buffer);

  pclose(gccStdin);

  free(buffer);
}

hw.c

#include <stdio.h>

int main() {

  char text[] = "hello world";
  printf("%s\n", text);

  return 0;
}

hw.x

#include <stdio.h>

int main() {

  uint1 text[] = "hello world";
  printf("%s\n", text);

  return 0;
}

xcompiler.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(int argc, char *argv[]){
  // We need 4 arguments "program source -o binary"
  if(argc < 4){
    printf("Insufficient arguments\n");
    return 1;
  }

  char * sourceFilename = argv[1];
  char * destFilename = argv[3];

  FILE * inputFile = fopen(sourceFilename, "r");

  if(inputFile == NULL){
    printf("File does not exist");
    return 1;
  }


  // Get source file size
  fseek(inputFile, 0 , SEEK_END);
  int sourceFileSize = ftell(inputFile);
  rewind(inputFile);

  // Read source file into buffer with one extra byte to accomodate '\0'
  int actualBuffSizeRequired = sourceFileSize + 1;
  char * buffer = (char *) malloc(actualBuffSizeRequired);
  buffer[sourceFileSize] = '\0';
  int read = fread(buffer, sizeof(char), sourceFileSize, inputFile);
  fclose(inputFile);

  /* Our custom X language with uint1 data type */
  char newDataType[6] = {'u', 'i', 'n', 't', '1', '\0'};
  char * whereUint;

  //Replace all instances of uint1 with char
  while ((whereUint = strstr(buffer, newDataType)) != NULL){
    strncpy(whereUint, "char ", 5);
  }


  /* We pass the source code to GCC as the backend compiler */
  char compileCommand[500];

  // Generate compile command, tell GCC to assume C language and get source code via stdin
  snprintf(compileCommand, 500, "gcc -o %s -xc -", destFilename);

  FILE * gccStdin;
  gccStdin = popen(compileCommand, "w");

  // Pass source code to GCC via stdin
  fwrite(buffer, sizeof(char), sourceFileSize, gccStdin);

  // Print actual source code used in compilation for reference
  printf("%s\n", buffer);

  pclose(gccStdin);

  free(buffer);
}

xcompiler.x

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(int argc, uint1 *argv[]) {
  // We need 4 arguments "program source -o binary"
  if (argc < 4) {
    printf("Insufficient arguments\n");
    return 1;
  }

  uint1 * sourceFilename = argv[1];
  uint1 * destFilename = argv[3];

  FILE * inputFile = fopen(sourceFilename, "r");

  if (inputFile == NULL) {
    printf("File does not exist");
    return 1;
  }


  // Get source file size
  fseek(inputFile, 0 , SEEK_END);
  int sourceFileSize = ftell(inputFile);
  rewind(inputFile);

  // Read source file into buffer with one extra byte to accomodate '\0'
  int actualBuffSizeRequired = sourceFileSize + 1;
  uint1 * buffer = (uint1 *) malloc(actualBuffSizeRequired);
  buffer[sourceFileSize] = '\0';
  int read = fread(buffer, sizeof(uint1), sourceFileSize, inputFile);
  fclose(inputFile);

  /* Our custom X language with uint1 data type */
  uint1 newDataType[6] = {'u', 'i', 'n', 't', '1', '\0'};
  uint1 * whereUint;

  // Replace all instances of uint1 with char
  while ((whereUint = strstr(buffer, newDataType)) != NULL) {
    strncpy(whereUint, "char ", 5);
  }


  /* We pass the source code to GCC as the backend compiler */
  uint1 compileCommand[500];

  //Generate compile command, tell GCC to assume C language and get source code via stdin
  snprintf(compileCommand, 500, "gcc -o %s -xc -", destFilename);

  FILE * gccStdin;
  gccStdin = popen(compileCommand, "w");

  //Pass source code to GCC via stdin
  fwrite(buffer, sizeof(uint1), sourceFileSize, gccStdin);

  //Print actual source code used in compilation for reference
  printf("%s\n", buffer);

  pclose(gccStdin);

  free(buffer);
}