diff options
Diffstat (limited to 'argv-array.h')
-rw-r--r-- | argv-array.h | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/argv-array.h b/argv-array.h index a39ba43f57ce..a7d3b107077a 100644 --- a/argv-array.h +++ b/argv-array.h @@ -1,8 +1,32 @@ #ifndef ARGV_ARRAY_H #define ARGV_ARRAY_H +/** + * The argv-array API allows one to dynamically build and store + * NULL-terminated lists. An argv-array maintains the invariant that the + * `argv` member always points to a non-NULL array, and that the array is + * always NULL-terminated at the element pointed to by `argv[argc]`. This + * makes the result suitable for passing to functions expecting to receive + * argv from main(). + * + * The string-list API (documented in string-list.h) is similar, but cannot be + * used for these purposes; instead of storing a straight string pointer, + * it contains an item structure with a `util` field that is not compatible + * with the traditional argv interface. + * + * Each `argv_array` manages its own memory. Any strings pushed into the + * array are duplicated, and all memory is freed by argv_array_clear(). + */ + extern const char *empty_argv[]; +/** + * A single array. This should be initialized by assignment from + * `ARGV_ARRAY_INIT`, or by calling `argv_array_init`. The `argv` + * member contains the actual array; the `argc` member contains the + * number of elements in the array, not including the terminating + * NULL. + */ struct argv_array { const char **argv; int argc; @@ -11,17 +35,55 @@ struct argv_array { #define ARGV_ARRAY_INIT { empty_argv, 0, 0 } +/** + * Initialize an array. This is no different than assigning from + * `ARGV_ARRAY_INIT`. + */ void argv_array_init(struct argv_array *); + +/* Push a copy of a string onto the end of the array. */ const char *argv_array_push(struct argv_array *, const char *); + +/** + * Format a string and push it onto the end of the array. This is a + * convenience wrapper combining `strbuf_addf` and `argv_array_push`. + */ __attribute__((format (printf,2,3))) const char *argv_array_pushf(struct argv_array *, const char *fmt, ...); + +/** + * Push a list of strings onto the end of the array. The arguments + * should be a list of `const char *` strings, terminated by a NULL + * argument. + */ LAST_ARG_MUST_BE_NULL void argv_array_pushl(struct argv_array *, ...); + +/* Push a null-terminated array of strings onto the end of the array. */ void argv_array_pushv(struct argv_array *, const char **); + +/** + * Remove the final element from the array. If there are no + * elements in the array, do nothing. + */ void argv_array_pop(struct argv_array *); + /* Splits by whitespace; does not handle quoted arguments! */ void argv_array_split(struct argv_array *, const char *); + +/** + * Free all memory associated with the array and return it to the + * initial, empty state. + */ void argv_array_clear(struct argv_array *); + +/** + * Disconnect the `argv` member from the `argv_array` struct and + * return it. The caller is responsible for freeing the memory used + * by the array, and by the strings it references. After detaching, + * the `argv_array` is in a reinitialized state and can be pushed + * into again. + */ const char **argv_array_detach(struct argv_array *); #endif /* ARGV_ARRAY_H */ |