Added new port TinyBasic

(An improved version in conjunction with ktcc can generate executable files.)

git-svn-id: svn://kolibrios.org@8733 a494cfbc-eb01-0410-851d-a64ba20cac60

programs/develop/tinybasic-1.0.4/src/errors.c

@@ -0,0 +1,223 @@
+/*
+ * Tiny BASIC
+ * Error Handling Module
+ *
+ * Released as Public Domain by Damian Gareth Walker 2019
+ * Created: 18-Aug-2019
+ */
+
+
+/* included headers */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "errors.h"
+
+
+/*
+ * Internal Data Structures
+ */
+
+
+/* Private data */
+typedef struct {
+  ErrorCode error; /* the last error encountered */
+  int line; /* the source line on which the error occurred */
+  int label; /* the label for the source line */
+} Private;
+
+
+/*
+ * Internal Data
+ */
+
+
+/* convenience variables */
+ErrorHandler *this; /* object being worked on */
+Private *data; /* private data of object being worked on */
+
+/* global variables */
+static char *messages[E_LAST] = { /* the error messages */
+  "Successful",
+  "Invalid line number",
+  "Unrecognised command",
+  "Invalid variable",
+  "Invalid assignment",
+  "Invalid expression",
+  "Missing )",
+  "Invalid PRINT output",
+  "Bad command line",
+  "File not found",
+  "Invalid operator",
+  "THEN expected",
+  "Unexpected parameter",
+  "RETURN without GOSUB",
+  "Divide by zero",
+  "Overflow",
+  "Out of memory",
+  "Too many gosubs"
+};
+
+
+/*
+ * Public Methods
+ */
+
+
+/*
+ * Record an error encountered
+ * globals:
+ *   ErrorCode   error       the last error encountered
+ *   int         line        the source line
+ *   int         label       the line's label
+ * params:
+ *   ErrorCode   new_error   the error code to set
+ *   int         new_line    the source line to set
+ *   int         new_label   the label to set
+ */
+static void set_code (ErrorHandler *errors, ErrorCode new_error, int new_line,
+  int new_label) {
+
+  /* initialise */
+  this = errors;
+  data = this->data;
+
+  /* set the properties */
+  data->error = new_error;
+  data->line = new_line;
+  data->label = new_label;
+}
+
+/*
+ * Return the last error code encountered
+ * params:
+ *   ErrorHandler*   errors   the error handler
+ * returns:
+ *   ErrorCode                the last error encountered
+ */
+static ErrorCode get_code (ErrorHandler *errors) {
+  this = errors;
+  data = this->data;
+  return data->error;
+}
+
+/*
+ * Return the last error line encountered
+ * params:
+ *   ErrorHandler*   errors   the error handler
+ * returns:
+ *   int                      the source line of the last error
+ */
+static int get_line (ErrorHandler *errors) {
+  this = errors;
+  data = this->data;
+  return data->line;
+}
+
+/*
+ * Return the last error label encountered
+ * params:
+ *   ErrorHandler*   errors   the error handler
+ * returns:
+ *   int                      the line label of the last error
+ */
+static int get_label (ErrorHandler *errors) {
+  this = errors;
+  data = this->data;
+  return data->label;
+}
+
+/*
+ * Generate an error message
+ * params:
+ *   ErrorHandler*   errors     the error handler
+ * globals:
+ *   char*           messages   a list of error messages
+ * returns:
+ *   char*                      the full error message
+ */
+static char *get_text (ErrorHandler *errors) {
+
+  /* local variables */
+  char
+    *message, /* the complete message */
+    *line_text, /* source line N */
+    *label_text; /* label N */
+
+  /* initialise the error object */
+  this = errors;
+  data = this->data;
+
+  /* get the source line, if there is one */
+  line_text = malloc (20);
+  if (data->line)
+    sprintf (line_text, ", source line %d", data->line);
+  else
+    strcpy (line_text, "");
+
+  /* get the source label, if there is one */
+  label_text = malloc (19);
+  if (data->label)
+    sprintf (label_text, ", line label %d", data->label);
+  else
+    strcpy (label_text, "");
+
+  /* put the error message together */
+  message = malloc (strlen (messages[data->error]) + strlen (line_text)
+    + strlen (label_text) + 1);
+  strcpy (message, messages[data->error]);
+  strcat (message, line_text);
+  strcat (message, label_text);
+  free (line_text);
+  free (label_text);
+
+  /* return the assembled error message */
+  return message;
+}
+
+/*
+ * ErrorHandler destructor
+ * params:
+ *   ErrorHandler*   errors   the doomed error handler
+ */
+static void destroy (ErrorHandler *errors) {
+  if ((this = errors)) {
+    data = this->data;
+    free (data);
+    free (this);
+  }
+}
+
+
+/*
+ * Constructors
+ */
+
+
+/*
+ * Principal constructor
+ * returns:
+ *   ErrorHandler*   the new error handler object
+ */
+ErrorHandler *new_ErrorHandler (void) {
+
+    /* allocate memory */
+    this = malloc (sizeof (ErrorHandler));
+    this->data = data = malloc (sizeof (Private));
+
+    /* initialise the methods */
+    this->set_code = set_code;
+    this->get_code = get_code;
+    this->get_line = get_line;
+    this->get_label = get_label;
+    this->get_text = get_text;
+    this->destroy = destroy;
+
+    /* initialise the properties */
+    data->error = E_NONE;
+    data->line = 0;
+    data->label = 0;
+
+    /* return the new object */
+    return this;
+}