#include "global.h"
static FILE *source_file;  /* the current input file */
static int source_peek;
static int double_at;
static int include_depth;
static struct {
  FILE *file;
  char *name;
  int line;
} stack[10];

int source_last;
int source_get(void)
{
  int c;
  source_last = c = source_peek;
  switch (c) {
    case EOF:  {
  fclose(source_file);
  if (include_depth) {
    include_depth--;
    source_file = stack[include_depth].file;
    source_line = stack[include_depth].line;
    source_name = stack[include_depth].name;
    source_peek = getc(source_file);
    c = source_get();
  }
}
               return c;
    case '@':  {
  c = getc(source_file);
  if (double_at) {
    source_peek = c;
    double_at = FALSE;
    c = '@';
  }
  else
    switch (c) {
      case 'i': {
  char name[100];
  if (include_depth >= 10) {
#ifdef _AMIGA
    fprintf(stderr, get_string(MSG_ERROR_42B1),
            command_name, source_name, source_line);
#else
    fprintf(stderr, "%s: include nesting too deep (%s, %d)\n",
            command_name, source_name, source_line);
#endif
    exit(EXIT_FAILURE);
  }
  {
    char *p = name;
    do
      c = getc(source_file);
    while (c == ' ' || c == '\t');
    while (isgraph(c)) {
      *p++ = c;
      c = getc(source_file);
    }
    *p = '\0';
    if (c != '\n') {
#ifdef _AMIGA
      fprintf(stderr, get_string(MSG_ERROR_43A),
              command_name, source_name, source_line);
#else
      fprintf(stderr, "%s: unexpected characters after file name (%s, %d)\n",
              command_name, source_name, source_line);
#endif
      exit(EXIT_FAILURE);
    }
}
  stack[include_depth].name = source_name;
  stack[include_depth].file = source_file;
  stack[include_depth].line = source_line + 1;
  include_depth++;
  source_line = 1;
  source_name = save_string(name);
  source_file = fopen(source_name, "r");
  if (!source_file) {
#ifdef _AMIGA
    fprintf(stderr, get_string(MSG_ERROR_42B2),
     command_name, source_name);
#else
    fprintf(stderr, "%s: can't open include file %s\n",
     command_name, source_name);
#endif
    exit(EXIT_FAILURE);
  }
  source_peek = getc(source_file);
  c = source_get();
}
                break;
      case 'f': case 'm': case 'u':
      case 'd': case 'o': case 'D': case 'O':
      case '{': case '}': case '<': case '>': case '|':
      case '(': case ')': case '[': case ']':
                source_peek = c;
                c = '@';
                break;
      case '@': source_peek = c;
                double_at = TRUE;
                break;
#ifdef _AMIGA
      default:  fprintf(stderr, get_string(MSG_ERROR_42A),
                        command_name, source_name, source_line);
#else
      default:  fprintf(stderr, "%s: bad @ sequence (%s, line %d)\n",
                        command_name, source_name, source_line);
#endif
                exit(EXIT_FAILURE);
    }
}
               return c;
    case '\n': source_line++;
    default:   source_peek = getc(source_file);
               return c;
  }
}
void source_open(char *name)
{
  source_file = fopen(name, "r");
  if (!source_file) {
#ifdef _AMIGA
    fprintf(stderr, get_string(MSG_ERROR_43C), command_name, name);
#else
    fprintf(stderr, "%s: couldn't open %s\n", command_name, name);
#endif
    exit(EXIT_FAILURE);
  }
  source_name = name;
  source_line = 1;
  source_peek = getc(source_file);
  double_at = FALSE;
  include_depth = 0;
}