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Diffstat (limited to 'strvec.h')
-rw-r--r-- | strvec.h | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/strvec.h b/strvec.h new file mode 100644 index 0000000..9f55c87 --- /dev/null +++ b/strvec.h @@ -0,0 +1,91 @@ +#ifndef STRVEC_H +#define STRVEC_H + +/** + * The strvec API allows one to dynamically build and store + * NULL-terminated arrays of strings. A strvec maintains the invariant that the + * `items` member always points to a non-NULL array, and that the array is + * always NULL-terminated at the element pointed to by `items[nr]`. 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 `strvec` manages its own memory. Any strings pushed into the + * array are duplicated, and all memory is freed by strvec_clear(). + */ + +extern const char *empty_strvec[]; + +/** + * A single array. This should be initialized by assignment from + * `STRVEC_INIT`, or by calling `strvec_init`. The `items` + * member contains the actual array; the `nr` member contains the + * number of elements in the array, not including the terminating + * NULL. + */ +struct strvec { + const char **v; + size_t nr; + size_t alloc; +}; + +#define STRVEC_INIT { \ + .v = empty_strvec, \ +} + +/** + * Initialize an array. This is no different than assigning from + * `STRVEC_INIT`. + */ +void strvec_init(struct strvec *); + +/* Push a copy of a string onto the end of the array. */ +const char *strvec_push(struct strvec *, const char *); + +/** + * Format a string and push it onto the end of the array. This is a + * convenience wrapper combining `strbuf_addf` and `strvec_push`. + */ +__attribute__((format (printf,2,3))) +const char *strvec_pushf(struct strvec *, 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 strvec_pushl(struct strvec *, ...); + +/* Push a null-terminated array of strings onto the end of the array. */ +void strvec_pushv(struct strvec *, const char **); + +/** + * Remove the final element from the array. If there are no + * elements in the array, do nothing. + */ +void strvec_pop(struct strvec *); + +/* Splits by whitespace; does not handle quoted arguments! */ +void strvec_split(struct strvec *, const char *); + +/** + * Free all memory associated with the array and return it to the + * initial, empty state. + */ +void strvec_clear(struct strvec *); + +/** + * Disconnect the `items` member from the `strvec` 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 `strvec` is in a reinitialized state and can be pushed + * into again. + */ +const char **strvec_detach(struct strvec *); + +#endif /* STRVEC_H */ |