X-Git-Url: http://git.efficios.com/?p=argpar.git;a=blobdiff_plain;f=argpar%2Fargpar.h;h=45dd84ed9d493d0bfb5208bfada2a7ed25750938;hp=00334cd6fb9d6f0c14a7fc08f5a21d114e778e65;hb=fc07e5264804963a3de6d1b929a9eb4fd37e49d4;hpb=a99ee691baf201d91c8a2f7e727de22e9d4b8bb5 diff --git a/argpar/argpar.h b/argpar/argpar.h index 00334cd..45dd84e 100644 --- a/argpar/argpar.h +++ b/argpar/argpar.h @@ -1,7 +1,8 @@ /* * SPDX-License-Identifier: MIT * - * Copyright 2019 Philippe Proulx + * Copyright (c) 2019-2021 Philippe Proulx + * Copyright (c) 2020-2021 Simon Marchi */ #ifndef BABELTRACE_ARGPAR_H @@ -9,15 +10,106 @@ #include +/* + * argpar is a library which provides facilities for command-line + * argument parsing. + * + * Two APIs are available: + * + * Iterator API: + * Create a parsing iterator with argpar_iter_create(), then + * repeatedly call argpar_iter_parse_next() to access the parsing + * results, until one of: + * + * * There are no more arguments. + * + * * The argument parser encounters an error (for example, an + * unknown option). + * + * * You need to stop. + * + * This API provides more parsing control than the next one. + * + * Single call API: + * Call argpar_parse(), which parses the arguments until one of: + * + * * There are no more arguments. + * + * * It encounters an argument parsing error. + * + * argpar_parse() returns a single array of parsing results. + * + * Both methods parse the arguments `argv` of which the count is `argc` + * using the sentinel-terminated (use `ARGPAR_OPT_DESCR_SENTINEL`) + * option descriptor array `descrs`. + * + * argpar considers ALL the elements of `argv`, including the first one, + * so that you would typically pass `argc - 1` and `&argv[1]` from what + * main() receives. + * + * The argpar parsers support: + * + * * Short options without an argument, possibly tied together: + * + * -f -auf -n + * + * * Short options with argument: + * + * -b 45 -f/mein/file -xyzhello + * + * * Long options without an argument: + * + * --five-guys --burger-king --pizza-hut --subway + * + * * Long options with arguments: + * + * --security enable --time=18.56 + * + * * Non-option arguments (anything else). + * + * The argpar parsers don't accept `-` or `--` as arguments. The latter + * means "end of options" for many command-line tools, but this library + * is all about keeping the order of the arguments, so it doesn't mean + * much to put them at the end. This has the side effect that a + * non-option argument cannot have the form of an option, for example if + * you need to pass the exact relative path `--component`. In that case, + * you would need to pass `./--component`. There's no generic way to + * escape `-` as of this version. + * + * Both argpar_iter_create() and argpar_parse() accept duplicate options + * (they produce one item for each instance). + * + * A returned parsing item has the type `struct argpar_item *`. Each + * item is to be casted to the appropriate type + * (`struct argpar_item_opt *` or `struct argpar_item_non_opt *`) + * depending on its `type` member. + * + * Both argpar_iter_create() and argpar_parse() produce the items in + * the same order that the arguments were parsed, including non-option + * arguments. This means, for example, that for: + * + * --hello --count=23 /path/to/file -ab --type file magie + * + * The produced items are, in this order: + * + * 1. Option item (`--hello`). + * 2. Option item (`--count` with argument `23`). + * 3. Non-option item (`/path/to/file`). + * 4. Option item (`-a`). + * 5. Option item (`-b`). + * 6. Option item (`--type` with argument `file`). + * 7. Non-option item (`magie`). + */ + /* Sentinel for an option descriptor array */ #define ARGPAR_OPT_DESCR_SENTINEL { -1, '\0', NULL, false } /* - * ARGPAR_HIDDEN: if argpar is used in some shared library, we don't want them - * to be exported by that library, so mark them as "hidden". + * ARGPAR_HIDDEN: if argpar is used in some shared library, we don't + * want them to be exported by that library, so mark them as "hidden". * - * On Windows, symbols are local unless explicitly exported, - * see https://gcc.gnu.org/wiki/Visibility + * On Windows, symbols are local unless explicitly exported; see + * . */ #if defined(_WIN32) || defined(__CYGWIN__) #define ARGPAR_HIDDEN @@ -25,6 +117,9 @@ #define ARGPAR_HIDDEN __attribute__((visibility("hidden"))) #endif +/* Forward-declaration for the opaque type */ +struct argpar_iter; + /* Option descriptor */ struct argpar_opt_descr { /* Numeric ID for this option */ @@ -95,7 +190,13 @@ struct argpar_item_array { /* What is returned by argpar_parse() */ struct argpar_parse_ret { - /* Array of `struct argpar_item *`, or `NULL` on error */ + /* + * Array of `struct argpar_item *`, or `NULL` on error. + * + * Do NOT destroy those items manually with + * argpar_iter_destroy(): call argpar_parse_ret_fini() to + * finalize the whole structure. + */ struct argpar_item_array *items; /* Error string, or `NULL` if none */ @@ -106,63 +207,17 @@ struct argpar_parse_ret { }; /* - * Parses the arguments `argv` of which the count is `argc` using the - * sentinel-terminated (use `ARGPAR_OPT_DESCR_SENTINEL`) option - * descriptor array `descrs`. - * - * This function considers ALL the elements of `argv`, including the - * first one, so that you would typically pass `argc - 1` and - * `&argv[1]` from what main() receives. + * Parses arguments in `argv` until the end is reached or an error is + * encountered. * - * This argument parser supports: - * - * * Short options without an argument, possibly tied together: - * - * -f -auf -n - * - * * Short options with argument: - * - * -b 45 -f/mein/file -xyzhello - * - * * Long options without an argument: - * - * --five-guys --burger-king --pizza-hut --subway - * - * * Long options with arguments: - * - * --security enable --time=18.56 - * - * * Non-option arguments (anything else). - * - * This function does not accept `-` or `--` as arguments. The latter - * means "end of options" for many command-line tools, but this function - * is all about keeping the order of the arguments, so it does not mean - * much to put them at the end. This has the side effect that a - * non-option argument cannot have the form of an option, for example if - * you need to pass the exact relative path `--component`. In that case, - * you would need to pass `./--component`. There's no generic way to - * escape `-` for the moment. - * - * This function accepts duplicate options (the resulting array of items - * contains one entry for each instance). - * - * On success, this function returns an array of items - * (`struct argpar_item *`). Each item is to be casted to the - * appropriate type (`struct argpar_item_opt *` or - * `struct argpar_item_non_opt *`) depending on its type. - * - * The returned array contains the items in the same order that the - * arguments were parsed, including non-option arguments. This means, - * for example, that for - * - * --hello --meow=23 /path/to/file -b - * - * the function returns an array of four items: two options, one - * non-option, and one option. + * On success, this function returns an array of items (field `items` of + * `struct argpar_parse_ret`). * * In the returned structure, `ingested_orig_args` is the number of * ingested arguments within `argv` to produce the resulting array of - * items. If `fail_on_unknown_opt` is true, then on success + * items. + * + * If `fail_on_unknown_opt` is true, then on success * `ingested_orig_args` is equal to `argc`. Otherwise, * `ingested_orig_args` contains the number of original arguments until * an unknown _option_ occurs. For example, with @@ -193,11 +248,10 @@ struct argpar_parse_ret { * for example contains two ingested original arguments, but four * resulting items. * - * On failure, the returned structure's `items` member is `NULL`, and - * the `error` string member contains details about the error. + * On failure, the `items` member of the returned structure is `NULL`, + * and the `error` string member contains details about the error. * - * You can finalize the returned structure with - * argpar_parse_ret_fini(). + * Finalize the returned structure with argpar_parse_ret_fini(). */ ARGPAR_HIDDEN struct argpar_parse_ret argpar_parse(unsigned int argc, @@ -206,12 +260,90 @@ struct argpar_parse_ret argpar_parse(unsigned int argc, bool fail_on_unknown_opt); /* - * Finalizes what is returned by argpar_parse(). + * Finalizes what argpar_parse() returns. * - * It is safe to call argpar_parse() multiple times with the same - * structure. + * You may call argpar_parse() multiple times with the same structure. */ ARGPAR_HIDDEN void argpar_parse_ret_fini(struct argpar_parse_ret *ret); +/* + * Creates an argument parsing iterator. + * + * This function initializes the returned structure, but doesn't + * actually start parsing the arguments. + * + * `*argv` and `*descrs` must NOT change for the lifetime of the + * returned iterator (until you call argpar_iter_destroy()). + * + * Call argpar_iter_parse_next() with the returned iterator to obtain + * the next parsing result (item). + */ +ARGPAR_HIDDEN +struct argpar_iter *argpar_iter_create(unsigned int argc, + const char * const *argv, + const struct argpar_opt_descr *descrs); + +/* + * Destroys `iter`, as returned by argpar_iter_create(). + */ +ARGPAR_HIDDEN +void argpar_iter_destroy(struct argpar_iter *iter); + +/* + * Return type of argpar_iter_parse_next(). + */ +enum argpar_iter_parse_next_status { + ARGPAR_ITER_PARSE_NEXT_STATUS_OK, + ARGPAR_ITER_PARSE_NEXT_STATUS_END, + ARGPAR_ITER_PARSE_NEXT_STATUS_ERROR_UNKNOWN_OPT, + ARGPAR_ITER_PARSE_NEXT_STATUS_ERROR, +}; + +/* + * Parses and returns the next item from `iter`. + * + * On success, this function sets `*item` to an item which describes the + * next option or non-option argument and returns + * `ARGPAR_ITER_PARSE_NEXT_STATUS_OK`. Destroy `*item` with + * argpar_item_destroy(). + * + * If there are no more items to return, this function returns + * `ARGPAR_ITER_PARSE_NEXT_STATUS_END`. + * + * On failure (status codes + * `ARGPAR_ITER_PARSE_NEXT_STATUS_ERROR_UNKNOWN_OPT` and + * `ARGPAR_ITER_PARSE_NEXT_STATUS_ERROR`), this function sets `*error` + * to a descriptive error string. Free `*error` with free(). + * + * Create an argument parsing iterator with argpar_iter_create(). + */ +enum argpar_iter_parse_next_status argpar_iter_parse_next( + struct argpar_iter *iter, const struct argpar_item **item, + char **error); + +/* + * Returns the number of ingested elements from `argv`, as passed to + * argpar_iter_create() to create `*iter`, that were required to produce + * the previously returned items. + */ +ARGPAR_HIDDEN +unsigned int argpar_iter_get_ingested_orig_args(const struct argpar_iter *iter); + +/* + * Destroys `item`, as created by argpar_iter_parse_next(). + */ +ARGPAR_HIDDEN +void argpar_item_destroy(const struct argpar_item *item); + +/* + * Destroys `_item` (`const struct argpar_item *`) and sets it to + * `NULL`. + */ +#define ARGPAR_ITEM_DESTROY_AND_RESET(_item) \ + { \ + argpar_item_destroy(_item); \ + _item = NULL; \ + } + #endif /* BABELTRACE_ARGPAR_H */