From d377b707b67b477ee5b22b08c714be34f3e82aa3 Mon Sep 17 00:00:00 2001 From: sanine-a Date: Fri, 7 Apr 2023 13:59:47 -0500 Subject: switch to cargs and remove honeysuckle --- src/cargs/cargs.c | 437 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 437 insertions(+) create mode 100644 src/cargs/cargs.c (limited to 'src/cargs/cargs.c') diff --git a/src/cargs/cargs.c b/src/cargs/cargs.c new file mode 100644 index 0000000..9f0ff7f --- /dev/null +++ b/src/cargs/cargs.c @@ -0,0 +1,437 @@ +#include +#include "cargs.h" +#include +#include +#include + +#define CAG_OPTION_PRINT_DISTANCE 4 +#define CAG_OPTION_PRINT_MIN_INDENTION 20 + +static void cag_option_print_value(const cag_option *option, + size_t *accessor_length, FILE *destination) +{ + if (option->value_name != NULL) { + *accessor_length += fprintf(destination, "=%s", option->value_name); + } +} + +static void cag_option_print_letters(const cag_option *option, bool *first, + size_t *accessor_length, FILE *destination) +{ + const char *access_letter; + access_letter = option->access_letters; + if (access_letter != NULL) { + while (*access_letter) { + if (*first) { + *accessor_length += fprintf(destination, "-%c", *access_letter); + *first = false; + } else { + *accessor_length += fprintf(destination, ", -%c", *access_letter); + } + ++access_letter; + } + } +} + +static void cag_option_print_name(const cag_option *option, bool *first, + size_t *accessor_length, FILE *destination) +{ + if (option->access_name != NULL) { + if (*first) { + *accessor_length += fprintf(destination, "--%s", option->access_name); + } else { + *accessor_length += fprintf(destination, ", --%s", option->access_name); + } + } +} + +static size_t cag_option_get_print_indention(const cag_option *options, + size_t option_count) +{ + size_t option_index, indention, result; + const cag_option *option; + + result = CAG_OPTION_PRINT_MIN_INDENTION; + + for (option_index = 0; option_index < option_count; ++option_index) { + indention = CAG_OPTION_PRINT_DISTANCE; + option = &options[option_index]; + if (option->access_letters != NULL && *option->access_letters) { + indention += strlen(option->access_letters) * 4 - 2; + if (option->access_name != NULL) { + indention += strlen(option->access_name) + 4; + } + } else if (option->access_name != NULL) { + indention += strlen(option->access_name) + 2; + } + + if (option->value_name != NULL) { + indention += strlen(option->value_name) + 1; + } + + if (indention > result) { + result = indention; + } + } + + return result; +} + +void cag_option_print(const cag_option *options, size_t option_count, + FILE *destination) +{ + size_t option_index, indention, i, accessor_length; + const cag_option *option; + bool first; + + indention = cag_option_get_print_indention(options, option_count); + + for (option_index = 0; option_index < option_count; ++option_index) { + option = &options[option_index]; + accessor_length = 0; + first = true; + + fputs(" ", destination); + + cag_option_print_letters(option, &first, &accessor_length, destination); + cag_option_print_name(option, &first, &accessor_length, destination); + cag_option_print_value(option, &accessor_length, destination); + + for (i = accessor_length; i < indention; ++i) { + fputs(" ", destination); + } + + fputs(" ", destination); + fputs(option->description, destination); + + fprintf(destination, "\n"); + } +} + +void cag_option_prepare(cag_option_context *context, const cag_option *options, + size_t option_count, int argc, char **argv) +{ + // This just initialized the values to the beginning of all the arguments. + context->options = options; + context->option_count = option_count; + context->argc = argc; + context->argv = argv; + context->index = 1; + context->inner_index = 0; + context->forced_end = false; +} + +static const cag_option *cag_option_find_by_name(cag_option_context *context, + char *name, size_t name_size) +{ + const cag_option *option; + size_t i; + + // We loop over all the available options and stop as soon as we have found + // one. We don't use any hash map table, since there won't be that many + // arguments anyway. + for (i = 0; i < context->option_count; ++i) { + option = &context->options[i]; + + // The option might not have an item name, we can just skip those. + if (option->access_name == NULL) { + continue; + } + + // Try to compare the name of the access name. We can use the name_size or + // this comparison, since we are guaranteed to have null-terminated access + // names. + if (strncmp(option->access_name, name, name_size) == 0) { + return option; + } + } + + return NULL; +} + +static const cag_option *cag_option_find_by_letter(cag_option_context *context, + char letter) +{ + const cag_option *option; + size_t i; + + // We loop over all the available options and stop as soon as we have found + // one. We don't use any look up table, since there won't be that many + // arguments anyway. + for (i = 0; i < context->option_count; ++i) { + option = &context->options[i]; + + // If this option doesn't have any access letters we will skip them. + if (option->access_letters == NULL) { + continue; + } + + // Verify whether this option has the access letter in it's access letter + // string. If it does, then this is our option. + if (strchr(option->access_letters, letter) != NULL) { + return option; + } + } + + return NULL; +} + +static void cag_option_parse_value(cag_option_context *context, + const cag_option *option, char **c) +{ + // And now let's check whether this option is supposed to have a value, which + // is the case if there is a value name set. The value can be either submitted + // with a '=' sign or a space, which means we would have to jump over to the + // next argv index. This is somewhat ugly, but we do it to behave the same as + // the other option parsers. + if (option->value_name != NULL) { + if (**c == '=') { + context->value = ++(*c); + } else { + // If the next index is larger or equal to the argument count, then the + // parameter for this option is missing. The user will know about this, + // since the value pointer of the context will be NULL because we don't + // set it here in that case. + if (context->argc > context->index + 1) { + // We consider this argv to be the value, no matter what the contents + // are. + ++context->index; + *c = context->argv[context->index]; + context->value = *c; + } + } + + // Move c to the end of the value, to not confuse the caller about our + // position. + while (**c) { + ++(*c); + } + } +} + +static void cag_option_parse_access_name(cag_option_context *context, char **c) +{ + const cag_option *option; + char *n; + + // Now we need to extract the access name, which is any symbol up to a '=' or + // a '\0'. + n = *c; + while (**c && **c != '=') { + ++*c; + } + + // Now this will obviously always be true, but we are paranoid. Sometimes. It + // doesn't hurt to check. + assert(*c >= n); + + // Figure out which option this name belongs to. This might return NULL if the + // name is not registered, which means the user supplied an unknown option. In + // that case we return true to indicate that we finished with this option. We + // have to skip the value parsing since we don't know whether the user thinks + // this option has one or not. Since we don't set any identifier specifically, + // it will remain '?' within the context. + option = cag_option_find_by_name(context, n, (size_t)(*c - n)); + if (option == NULL) { + // Since this option is invalid, we will move on to the next index. There is + // nothing we can do about this. + ++context->index; + return; + } + + // We found an option and now we can specify the identifier within the + // context. + context->identifier = option->identifier; + + // And now we try to parse the value. This function will also check whether + // this option is actually supposed to have a value. + cag_option_parse_value(context, option, c); + + // And finally we move on to the next index. + ++context->index; +} + +static void cag_option_parse_access_letter(cag_option_context *context, + char **c) +{ + const cag_option *option; + char *n = *c; + char *v; + + // Figure out which option this letter belongs to. This might return NULL if + // the letter is not registered, which means the user supplied an unknown + // option. In that case we return true to indicate that we finished with this + // option. We have to skip the value parsing since we don't know whether the + // user thinks this option has one or not. Since we don't set any identifier + // specifically, it will remain '?' within the context. + option = cag_option_find_by_letter(context, n[context->inner_index]); + if (option == NULL) { + ++context->index; + context->inner_index = 0; + return; + } + + // We found an option and now we can specify the identifier within the + // context. + context->identifier = option->identifier; + + // And now we try to parse the value. This function will also check whether + // this option is actually supposed to have a value. + v = &n[++context->inner_index]; + cag_option_parse_value(context, option, &v); + + // Check whether we reached the end of this option argument. + if (*v == '\0') { + ++context->index; + context->inner_index = 0; + } +} + +static void cag_option_shift(cag_option_context *context, int start, int option, + int end) +{ + char *tmp; + int a_index, shift_index, shift_count, left_index, right_index; + + shift_count = option - start; + + // There is no shift is required if the start and the option have the same + // index. + if (shift_count == 0) { + return; + } + + // Lets loop through the option strings first, which we will move towards the + // beginning. + for (a_index = option; a_index < end; ++a_index) { + // First remember the current option value, because we will have to save + // that later at the beginning. + tmp = context->argv[a_index]; + + // Let's loop over all option values and shift them one towards the end. + // This will override the option value we just stored temporarily. + for (shift_index = 0; shift_index < shift_count; ++shift_index) { + left_index = a_index - shift_index; + right_index = a_index - shift_index - 1; + context->argv[left_index] = context->argv[right_index]; + } + + // Now restore the saved option value at the beginning. + context->argv[a_index - shift_count] = tmp; + } + + // The new index will be before all non-option values, in such a way that they + // all will be moved again in the next fetch call. + context->index = end - shift_count; +} + +static bool cag_option_is_argument_string(const char *c) +{ + return *c == '-' && *(c + 1) != '\0'; +} + +static int cag_option_find_next(cag_option_context *context) +{ + int next_index, next_option_index; + char *c; + + // Prepare to search the next option at the next index. + next_index = context->index; + next_option_index = next_index; + + // Grab a pointer to the string and verify that it is not the end. If it is + // the end, we have to return false to indicate that we finished. + c = context->argv[next_option_index]; + if (context->forced_end || c == NULL) { + return -1; + } + + // Check whether it is a '-'. We need to find the next option - and an option + // always starts with a '-'. If there is a string "-\0", we don't consider it + // as an option neither. + while (!cag_option_is_argument_string(c)) { + c = context->argv[++next_option_index]; + if (c == NULL) { + // We reached the end and did not find any argument anymore. Let's tell + // our caller that we reached the end. + return -1; + } + } + + // Indicate that we found an option which can be processed. The index of the + // next option will be returned. + return next_option_index; +} + +bool cag_option_fetch(cag_option_context *context) +{ + char *c; + int old_index, new_index; + + // Reset our identifier to a question mark, which indicates an "unknown" + // option. The value is set to NULL, to make sure we are not carrying the + // parameter from the previous option to this one. + context->identifier = '?'; + context->value = NULL; + + // Check whether there are any options left to parse and remember the old + // index as well as the new index. In the end we will move the option junk to + // the beginning, so that non option arguments can be read. + old_index = context->index; + new_index = cag_option_find_next(context); + if (new_index >= 0) { + context->index = new_index; + } else { + return false; + } + + // Grab a pointer to the beginning of the option. At this point, the next + // character must be a '-', since if it was not the prepare function would + // have returned false. We will skip that symbol and proceed. + c = context->argv[context->index]; + assert(*c == '-'); + ++c; + + // Check whether this is a long option, starting with a double "--". + if (*c == '-') { + ++c; + + // This might be a double "--" which indicates the end of options. If this + // is the case, we will not move to the next index. That ensures that + // another call to the fetch function will not skip the "--". + if (*c == '\0') { + context->forced_end = true; + } else { + // We parse now the access name. All information about it will be written + // to the context. + cag_option_parse_access_name(context, &c); + } + } else { + // This is no long option, so we can just parse an access letter. + cag_option_parse_access_letter(context, &c); + } + + // Move the items so that the options come first followed by non-option + // arguments. + cag_option_shift(context, old_index, new_index, context->index); + + return context->forced_end == false; +} + +char cag_option_get(const cag_option_context *context) +{ + // We just return the identifier here. + return context->identifier; +} + +const char *cag_option_get_value(const cag_option_context *context) +{ + // We just return the internal value pointer of the context. + return context->value; +} + +int cag_option_get_index(const cag_option_context *context) +{ + // Either we point to a value item, + return context->index; +} -- cgit v1.2.1