5cover/c-exceptions

Macros for throwing and handling exceptions in C, in a try/catch/finally-like fashion.

C-exCeptions

Static library containing macros for throwing and handling exceptions in C based on the C# syntax.

Unhandled exceptions result in a call to abort(). To respond to unhandled exceptions, the SIGABRT signal can be handled or a try/catchAll block can be defined in the main function.

Usage

Interface reference:

• throw: throw an exception
  1. id - ID of the exception. Can be an ExceptionID value or an integer.
  2. message - Message of the exception. Must be a string (char *).
• try: define a try block
• catch: catch an exception with a specific ID
  1. targetId - ID of the exception to catch. Can be an ExceptionID value or an integer.
  2. varName - Name of the variable (of type Exception const *const) that points the catched exception.
• catchWhen: catch an exception with a specific ID only when the provided boolean expression evaluates to true
  1. targetId - ID of the exception to catch. Can be an ExceptionID value or an integer.
  2. varName - Name of the variable (of type Exception const *const) that points the catched exception.
• catchAll: catch any exception
  1. varName - Name of the variable (of type Exception const *const) that points the catched exception.
• catchAllWhen: catch any exception when the provided boolean expression evaluates to true
  1. varName - Name of the variable (of type Exception const *const) that points the catched exception.
• rethrow: rethrow an exception from a catch block.
• finally: defines a block to execute regardless of whether an exception occured or not.

See the comments in example for a walk-through of the code.

Known issues

• The try macro cannot be used in a single-statement scope (i.e. if statement without braces). This is not a problem since it is useless without catch or finally blocks.
• An exception variable name has to be specified when defining a catch block. You can use _ as the identifier if you're not planning to use it. Unused variable warnings will be hidden if GNU C is supported (with the unused attribute).
• The try-catch stack is defined as thread-local, so exceptions will not bubble up outside of their original thread.

Reserved identifiers

All reserved identifiers are prefixed by _ex_.

Contributing

This is mostly an experiment with advanced macro features and the setjmp/longjmp.