Apache: The Definitive Guide, 3rd Edition

Name

Command Table

Synopsis

command_rec aCommands[]

This structure points to an array of directives that configure the module. Each entry names a directive, specifies a function that will handle the command, and specifies which AllowOverride directives must be in force for the command to be permitted. Each entry then specifies how the directive’s arguments are to be parsed and supplies an error message in case of syntax errors (such as the wrong number of arguments, or a directive used where it shouldn’t be).

The definition of command_rec can be found in http_config.h:

typedef struct command_struct {
  const char *name;          /* Name of this command */
  const char *(*func)();     /* Function invoked */
  void *cmd_data;            /* Extra data, for functions that
                              * implement multiple commands...
                              */
  int req_override;          /* What overrides need to be allowed to
                              * enable this command
                              */
  enum cmd_how args_how;     /* What the command expects as arguments */
  
  const char *errmsg;        /* 'usage' message, in case of syntax errors */
} command_rec;

Note that in 2.0 this definition is still broadly correct, but there’s also a variant for compilers that allow designated initializers to permit the type-safe initialization of command_recs.

cmd_how is defined as follows:

enum cmd_how { RAW_ARGS, /* cmd_func parses command line itself */ TAKE1, /* one argument only */ TAKE2, /* two arguments only */ ITERATE, /* one argument, occurring multiple times * (e.g., IndexIgnore) */ ITERATE2, /* two arguments, 2nd occurs multiple times * ...