Better makefile, restructured, more demos

Makefile

@@ -1,19 +1,23 @@
 CC=gcc
 LD=gcc
 EXECOBJ=
-OBJECTS=exclib.o exception_test.o
+LIBOBJECTS=src/exclib.o
+DEMOS=demo/single.exe demo/twolevel.exe demo/threelevel.exe demo/trypair.exe
+LIBTARGET=lib/libexc.a
 LIBS=
 CFLAGS=
 
-all: exception_test
+all: $(LIBTARGET) $(DEMOS)
+
+demo/%.exe: demo/%.o
+	$(LD) -o $@ $(CFLAGS) -L./lib $< -lexc -ggdb -gstabs
 
 %.o: %.c
-	$(CC) -c -o $@ $(CFLAGS) -rdynamic -ggdb -gstabs $<
+	$(CC) -c -o $@ $(CFLAGS) -ggdb -gstabs -I./include $<
 
-exception_test: $(OBJECTS)
-	$(LD) -o exception_test $(LIBS) $(OBJECTS)
+$(LIBTARGET): $(LIBOBJECTS)
+	ar rcs $(LIBTARGET) $(LIBOBJECTS)
 
 .PHONY: clean
 clean:
-	rm -f *.o
-	rm -f exception_test
+	rm -f demo/*o $(LIBOBJECTS) $(DEMOS) $(LIBTARGET)

demo/single.c

@@ -0,0 +1,23 @@
+#include "exclib.h"
+
+/*
+ * What this demo shows:
+ * 1- The general usage of this library
+ * 2- That a basic usage example works
+ */
+
+int main(void)
+{
+  EXCLIB_TRACE("No stack to print?");
+
+  TRY {
+    THROW(3, NULL);
+  } CATCH(3) {
+    EXCLIB_TRACE("Caught 3");
+  } ETRY;
+
+  EXCLIB_TRACE("Exiting program");
+
+  return 0;
+
+}

demo/threelevel.c

@@ -0,0 +1,16 @@
+#include "exclib.h"
+
+int main(void)
+{
+  TRY {
+    TRY {
+      THROW(3, NULL);
+    } CATCH(5) {
+      EXCLIB_TRACE("Caught 5");
+    } ETRY;
+  } CATCH(3) {
+    EXCLIB_TRACE("Caught 3");
+  } ETRY;
+
+  return 0;
+}

demo/trypair.c

@@ -0,0 +1,21 @@
+#include "exclib.h"
+
+int main(void)
+{
+  TRY {
+    THROW(3, NULL);
+  } CATCH(3) {
+  } ETRY;
+
+  TRY {
+    THROW(3, NULL);
+  } CATCH(3) {
+    TRY {
+      THROW(3, NULL);
+    } ETRY;
+  } ETRY;
+
+  EXCLIB_TRACE("Should never get here");
+  return 0;
+
+}

demo/twolevel.c

@@ -0,0 +1,21 @@
+#include "exclib.h"
+
+/*
+ * What this example shows:
+ * 1- That an exception will propagate up out of the current TRY/CATCH context
+ * 2- That an uncaught exception will generate an error
+ */
+
+int main(void)
+{
+  TRY {
+    THROW(3, NULL);
+  } CATCH(3) {
+    THROW(3, NULL);
+  } ETRY;
+
+  EXCLIB_TRACE("Should never get here");
+
+  return 0;
+
+}

exception_test.c

@@ -1,63 +0,0 @@
-#include "exclib.h"
-#include <stdio.h>
-
-void nullfunc(int *something)
-{
-    THROW_ZERO(something, EXC_NULLPOINTER, NULL);
-    printf("nullfunc got %d\n", *something);
-}
-
-void badfunc(void)
-{
-    // This function represents a function that you think you can trust; but there's a null
-    // pointer being passed here that you have no control over. Thankfully 'nullfunc' was
-    // written to be safe, so it will illustrate the usefulness of TRY/CATCH/ETRY.
-    int *ptr = NULL;
-    nullfunc(ptr);
-}
-
-void testfunc(void)
-{
-    THROW(34, "Random test exception");
-}
-
-int main(void)
-{
-    int x = 2;
-
-    printf("Stack frames are %d bytes in size\n\n", sizeof(struct exc_status));
-
-    TRY {
-	fprintf(stdout, "Throwing %d\n", x);
-	THROW(2, "First exception");
-    } CATCH(-1) {
-	printf("Caught -1\n");
-	THROW(1, "1 Exception");
-    } CATCH(1) {
-	printf("Caught 1\n");
-    } CATCH(2) {
-	printf("Caught 2\n");
-	TRY {
-	    testfunc();
-	} CATCH(34) {
-	    printf("Caught 34!\n");
-	    printf("Throwing 34 Back Out\n");
-	    THROW(34, "Second-layer exception 34");
-	} ETRY;
-    } CATCH(34) {
-	printf("Caught 34 in upper level!\n");
-	printf("Using THROW_NONZERO\n");
-	THROW_NONZERO(strcmp("a", "b"), 0, "String Compare Exception");
-    } FINALLY {
-	exclib_print_exception_stack("In finally clause", __FILE__, (char *)__func__, __LINE__);
-    } ETRY;
-
-    TRY {
-	badfunc();
-    } ETRY;
-
-    /*printf("\nThrowing an exception with no toplevel TRY block, which should stacktrace and kill us...\n\n");
-
-    THROW(34, "Bad Exception");*/
-    return 0;
-}

exception_test_simple.c

@@ -1,31 +0,0 @@
-#include "exclib.h"
-
-int main(void)
-{
-  EXCLIB_TRACE("No stack to print?");
-
-  TRY {
-    EXCLIB_TRACE("Inside TRY");
-    THROW(3, NULL);
-  } CATCH(3) {
-    EXCLIB_TRACE("Caught 3");
-    THROW(5, NULL);
-  } CATCH(5) {
-    EXCLIB_TRACE("Caught 5");
-    TRY {
-      THROW(6, NULL);
-    } CATCH (6) {
-      EXCLIB_TRACE("Caught 6");
-      THROW(7, NULL);
-    } ETRY;
-  } CATCH(7) {
-    EXCLIB_TRACE("Caught 7");
-  } FINALLY {
-    EXCLIB_TRACE("In finally clause");
-  } ETRY;
-
-  EXCLIB_TRACE("Exiting program");
-
-  return 0;
-
-}

include/exclib.h

@@ -2,14 +2,10 @@
 #define __EXCLIB_H__
 
 #include <setjmp.h>
-#ifdef WIN32
-#include "backtrace.h"
-#else
-#include <execinfo.h>
-#endif
 #include <signal.h>
 #include <string.h>
 #include <unistd.h>
+#include <stdlib.h>
 #include <sys/types.h>
 
 /*
@@ -134,12 +130,19 @@ __exc_curidx--;
 
 #define FINALLY \
 }; \
-if ( EXC_STATUS_LIST->caught ) {
+if ( EXC_STATUS_LIST && EXC_STATUS_LIST->caught ) {
 
 #define THROW_NONZERO(x, y, z) int rc = (x); if ( rc != 0 ) THROW(rc + y, z);
 #define THROW_ZERO(x, y, z) if ( (x) == 0 ) THROW(y, z);
 
-#define THROW(x, y) exclib_prep_throw(x, y, __FILE__, (char *)__func__, __LINE__); if ( EXC_STATUS_LIST ) { longjmp(EXC_STATUS_LIST->buf, x); } else { exclib_print_exception_stack("Unhandled Exception "#x"", __FILE__, (char *)__func__, __LINE__); };
+#define THROW(x, y) \
+exclib_prep_throw(x, y, __FILE__, (char *)__func__, __LINE__);	\
+if ( EXC_STATUS_LIST->value > 0 ) { \
+  longjmp(EXC_STATUS_LIST->buf, x); \
+} else { \
+  exclib_print_exception_stack("Uncaught Exception "#x"", __FILE__, (char *)__func__, __LINE__); \
+  exit(x); \
+}
 
 #define EXCLIB_TRACE(x) exclib_print_exception_stack(x, __FILE__, (char *)__func__, __LINE__)
 

src/exclib.c

@@ -40,7 +40,8 @@ void exclib_print_exception_stack(char *mbuf, char *file, char *func, int line)
 
     if ( ! cur )
 	fprintf(stderr, "EXCLIB: #0: No exception stack\n");
-    while ( cur != NULL ) {
+    else {
+      while ( cur != NULL ) {
 	memset((char *)&buf, 0, 256);
 	memset((char *)&flagbuf, 0, 256);
 	if ( cur->catching == 1) {
@@ -77,6 +78,7 @@ void exclib_print_exception_stack(char *mbuf, char *file, char *func, int line)
 	fprintf(stderr, "%s", (char *)&buf);
 	idx += 1;
 	cur = cur->prev;
+      }
     }
 }
 
@@ -123,6 +125,7 @@ void exclib_prep_throw(int value, char *msg, char *file, char *func, int line)
 {
     char stbuf[256];
     memset((char *)&stbuf, 0, 256);
+
     if ( EXC_STATUS_LIST && EXC_STATUS_LIST->tried == 1) {
 	sprintf((char *)&stbuf, "Tried to THROW %d but couldn't create new exception frame", value);
 	if ( EXC_STATUS_LIST->catching == 1 && EXC_STATUS_LIST->prev ) {
@@ -131,26 +134,21 @@ void exclib_prep_throw(int value, char *msg, char *file, char *func, int line)
 	    exit(value);
 	  }
 	  memcpy(EXC_STATUS_LIST->buf, EXC_STATUS_LIST->prev->buf, sizeof(jmp_buf));
-        } /*else if ( EXC_STATUS_LIST->catching == 1 && (EXC_STATUS_LIST->prev == NULL) ) {
-	  if ( exclib_new_exc_frame(&__exc_statuses[__exc_curidx++], file, func, line) ) {
-		exclib_print_exception_stack((char *)&stbuf, file, func, line);
-		exit(value);
-	  }
-	  EXCLIB_TRACE("Condition 2");
+        } else if ( EXC_STATUS_LIST->catching == 1 && (EXC_STATUS_LIST->prev == NULL) ) {
 	  exclib_clear_exc_frame();
-	  __exc_curidx--;
-	  } */ else {
+	  return;
+	} else {
 	  if ( exclib_new_exc_frame(EXC_STATUS_LIST, file, func, line) )
 	    exclib_print_exception_stack((char *)&stbuf, file, func, line);
 	}
 	EXC_STATUS_LIST->value = value;
 	EXC_STATUS_LIST->name = __exc_names[value];
 	EXC_STATUS_LIST->description = msg;
-    } else {
-	sprintf((char *)&stbuf, "Tried to THROW Exception %d but had no exception context. (Called outside of TRY block, or thrown while TRY was setting up?)", value);
-	exclib_print_exception_stack((char *)&stbuf, file, func, line);
-	exit(__exc_signals[value]);
+	return;
     }
+    sprintf((char *)&stbuf, "Tried to THROW Exception %d but had no exception context. (Called outside of TRY block, or thrown while TRY was setting up?)", value);
+    exclib_print_exception_stack((char *)&stbuf, file, func, line);
+    exit(__exc_signals[value]);
 }
 
 
@@ -189,7 +187,7 @@ int exclib_clear_exc_frame()
 	exit(1);
     }
     if ( es->prev )
-	es->prev->next = NULL;
+      es->prev->next = NULL;
     if ( es->value && !es->caught ) {
 	// thrown exception was unhandled - do we have anywhere else to go?
         if ( !es->prev ) {
@@ -198,23 +196,24 @@ int exclib_clear_exc_frame()
 	  exit(es->value);
 	  //kill(getpid(), SIGKILL);
 	} else if ( es->tried && es->prev && (es->catching == 0)) {
-	    // copy this exception up into the upper frame and siglongjmp back to that
-	    EXC_STATUS_LIST = es->prev;
-	    EXC_STATUS_LIST->caught = 0;
-	    memcpy(&EXC_STATUS_LIST->bt_frames, &es->bt_frames, (sizeof(void *)*EXC_BT_FRAMES));
-	    EXC_STATUS_LIST->file = es->file;
-	    EXC_STATUS_LIST->function = es->function;
-	    EXC_STATUS_LIST->line = es->line;
-	    EXC_STATUS_LIST->name = es->name;
-	    EXC_STATUS_LIST->description = es->description;
-	    THROW(es->value, es->description);
+	  // copy this exception up into the upper frame and siglongjmp back to that
+	  EXC_STATUS_LIST = es->prev;
+	  EXC_STATUS_LIST->caught = 0;
+	  memcpy(&EXC_STATUS_LIST->bt_frames, &es->bt_frames, (sizeof(void *)*EXC_BT_FRAMES));
+	  EXC_STATUS_LIST->file = es->file;
+	  EXC_STATUS_LIST->function = es->function;
+	  EXC_STATUS_LIST->line = es->line;
+	  EXC_STATUS_LIST->name = es->name;
+	  EXC_STATUS_LIST->description = es->description;
+	  int val = es->value;
+	  memset((void *)es, 0x00, sizeof(struct exc_status));
+	  THROW(val, EXC_STATUS_LIST->description);
 	}
     } else {
+      if ( es->prev) {
 	EXC_STATUS_LIST = es->prev;
-	es->value = 0;
-	es->caught = 0;
-	es->tried = 0;
-	es->catching = 0;
+      }
+      memset((void *)es, 0x00, sizeof(struct exc_status));
     }
 }