server.h

#ifndef SERVER_H
#define SERVER_H

#include <netinet/in.h>
#include <sys/types.h>

/*** Symbols defined in common.c.  ************************************/

/* The name of this program.  */
extern const char* program_name;

/* If nonzero, print verbose messages.  */
extern int verbose;

/* Like malloc, except aborts the program if allocation fails.  */
extern void* xmalloc (size_t size);

/* like realloc, except aborts the program if allocation fails.  */
extern void* xrealloc (void* ptr, size_t size);

/* Like strdup, except aborts the program if allocation fails.  */
extern char* xstrdup (const char* s);

/* Print an error message for a failed call OPERATION, using the value
 * of errno, and end the program.  */
extern void system_error (const char* operation);

/* Print an error message for failure involving CAUSE, including a
 * descriptive MESSAGE, and end the program.  */
extern void error (const char* cause, const char* message); 

/* return the directory containing the running program's executable.
 * The return value is a memory buffer that the caller must deallocate
 * using free.  This function calls abort on failure.  */
extern char* get_self_executable_directory ();

/*** Symbols defined in module.c **************************************/

/* An instance of a loaded server module.  */
struct server_module {
	/* The shared library handle corresponding to the loaded module.  */
	void* handle;
	/* A name describing the module. */
	const char* name;
	/* The function that generates the HTML reults for this module.  */
	void (* generate_function) (int);
};

/* The directory from which modules are loaded.  */
extern char* module_dir;

/* Attempt to load a server module with the name MODULE_PATH. If a
 * server module exists with this path, loads the module and returns a
 * server_module structure representing it.  Otherwise, return NULL.  */
extern struct server_module* module_open (const char* module_path);

/* Close a server module and deallocate the MODULE object.  */
extern void module_close (struct server_module* module);


/*** Symbols defined in server.c.  ************************************/

/* Run the server on LOCAL_ADDRESS and PORT. */
extern void server_run (struct in_addr local_address, uint16_t port);

#endif /* SERVER_H */