Initial data commit

Task/Exceptions/C/exceptions-1.c

@@ -0,0 +1,27 @@
+#include <setjmp.h>
+
+enum { MY_EXCEPTION = 1 }; /* any non-zero number */
+
+jmp_buf env;
+
+void foo()
+{
+  longjmp(env, MY_EXCEPTION); /* throw MY_EXCEPTION */
+}
+
+void call_foo()
+{
+  switch (setjmp(env)) {
+  case 0:                     /* try */
+    foo();
+    break;
+  case MY_EXCEPTION:          /* catch MY_EXCEPTION */
+    /* handle exceptions of type MY_EXCEPTION */
+    break;
+  default:
+    /* handle any type of exception not handled by above catches */
+    /* note: if this "default" section is not included, that would be equivalent to a blank "default" section */
+    /* i.e. any exception not caught above would be caught and ignored */
+    /* there is no way to "let the exception through" */
+  }
+}

Task/Exceptions/C/exceptions-2.c

@@ -0,0 +1,82 @@
+#include <stdio.h>
+#include <setjmp.h>
+#include <stdlib.h>
+
+enum exceptions {
+        EXCEPTION_1 = 1,
+        EXCEPTION_2,
+        EXCEPTION_3
+};
+
+
+#define throw(exception) do {                                   \
+                if (exp)                                        \
+                        longjmp(*exp, exception);               \
+                printf("uncaught exception %d\n", exception);   \
+                exit(exception);                                \
+        } while (0)
+
+#define try(block, catch_block)                 \
+{                                               \
+        jmp_buf *exception_outer = exp;         \
+        jmp_buf exception_inner;                \
+        exp = &exception_inner;                 \
+        int exception = setjmp(*exp);           \
+        if (!exception) {                       \
+                do block while(0);              \
+                exp = exception_outer;          \
+        } else {                                \
+                exp = exception_outer;          \
+                switch(exception) {             \
+                catch_block                     \
+                default:                        \
+                        throw(exception);       \
+                }                               \
+        }                                       \
+}
+
+#define catch(exception, block) \
+        case exception: do block while (0); break;
+
+
+#define throws  jmp_buf* exp
+
+// define a throwing function
+void g(throws) {
+        printf("g !\n");
+        throw(EXCEPTION_1);
+        printf("shouldnt b here\n");
+}
+
+void h(throws, int a)
+{
+        printf("h %d!\n", a);
+        throw(EXCEPTION_2);
+}
+
+void f(throws) {
+        try({
+                g(exp); // call g with intention to catch exceptions
+        },
+        catch(EXCEPTION_1, {
+                printf("exception 1\n");
+                h(exp, 50); // will throw exception 2 inside this catch block
+        }))
+}
+
+int main(int argc, char* argv[])
+{
+        throws = NULL; // define exception stack base
+        try({
+                f(exp);
+        },
+        catch(EXCEPTION_2, {
+                printf("exception 2\n");
+        })
+        catch(EXCEPTION_3, {
+                printf("exception 3\n");
+        }))
+
+        h(exp, 60); // will result in "uncaught exception"
+        return 0;
+}