cwalk path library

1 files changed, 499 insertions, 0 deletions

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+#pragma once
+
+#ifndef CWK_LIBRARY_H
+#define CWK_LIBRARY_H
+
+#include <stdbool.h>
+#include <stddef.h>
+
+#if defined(_WIN32) || defined(__CYGWIN__)
+#define CWK_EXPORT __declspec(dllexport)
+#define CWK_IMPORT __declspec(dllimport)
+#elif __GNUC__ >= 4
+#define CWK_EXPORT __attribute__((visibility("default")))
+#define CWK_IMPORT __attribute__((visibility("default")))
+#else
+#define CWK_EXPORT
+#define CWK_IMPORT
+#endif
+
+#if defined(CWK_SHARED)
+#if defined(CWK_EXPORTS)
+#define CWK_PUBLIC CWK_EXPORT
+#else
+#define CWK_PUBLIC CWK_IMPORT
+#endif
+#else
+#define CWK_PUBLIC
+#endif
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+/**
+ * A segment represents a single component of a path. For instance, on linux a
+ * path might look like this "/var/log/", which consists of two segments "var"
+ * and "log".
+ */
+struct cwk_segment
+{
+  const char *path;
+  const char *segments;
+  const char *begin;
+  const char *end;
+  size_t size;
+};
+
+/**
+ * The segment type can be used to identify whether a segment is a special
+ * segment or not.
+ *
+ * CWK_NORMAL - normal folder or file segment
+ * CWK_CURRENT - "./" current folder segment
+ * CWK_BACK - "../" relative back navigation segment
+ */
+enum cwk_segment_type
+{
+  CWK_NORMAL,
+  CWK_CURRENT,
+  CWK_BACK
+};
+
+/**
+ * @brief Determines the style which is used for the path parsing and
+ * generation.
+ */
+enum cwk_path_style
+{
+  CWK_STYLE_WINDOWS,
+  CWK_STYLE_UNIX
+};
+
+/**
+ * @brief Generates an absolute path based on a base.
+ *
+ * This function generates an absolute path based on a base path and another
+ * path. It is guaranteed to return an absolute path. If the second submitted
+ * path is absolute, it will override the base path. The result will be
+ * written to a buffer, which might be truncated if the buffer is not large
+ * enough to hold the full path. However, the truncated result will always be
+ * null-terminated. The returned value is the amount of characters which the
+ * resulting path would take if it was not truncated (excluding the
+ * null-terminating character).
+ *
+ * @param base The absolute base path on which the relative path will be
+ * applied.
+ * @param path The relative path which will be applied on the base path.
+ * @param buffer The buffer where the result will be written to.
+ * @param buffer_size The size of the result buffer.
+ * @return Returns the total amount of characters of the new absolute path.
+ */
+CWK_PUBLIC size_t cwk_path_get_absolute(const char *base, const char *path,
+  char *buffer, size_t buffer_size);
+
+/**
+ * @brief Generates a relative path based on a base.
+ *
+ * This function generates a relative path based on a base path and another
+ * path. It determines how to get to the submitted path, starting from the
+ * base directory. The result will be written to a buffer, which might be
+ * truncated if the buffer is not large enough to hold the full path. However,
+ * the truncated result will always be null-terminated. The returned value is
+ * the amount of characters which the resulting path would take if it was not
+ * truncated (excluding the null-terminating character).
+ *
+ * @param base_directory The base path from which the relative path will
+ * start.
+ * @param path The target path where the relative path will point to.
+ * @param buffer The buffer where the result will be written to.
+ * @param buffer_size The size of the result buffer.
+ * @return Returns the total amount of characters of the full path.
+ */
+CWK_PUBLIC size_t cwk_path_get_relative(const char *base_directory,
+  const char *path, char *buffer, size_t buffer_size);
+
+/**
+ * @brief Joins two paths together.
+ *
+ * This function generates a new path by combining the two submitted paths. It
+ * will remove double separators, and unlike cwk_path_get_absolute it permits
+ * the use of two relative paths to combine. The result will be written to a
+ * buffer, which might be truncated if the buffer is not large enough to hold
+ * the full path. However, the truncated result will always be
+ * null-terminated. The returned value is the amount of characters which the
+ * resulting path would take if it was not truncated (excluding the
+ * null-terminating character).
+ *
+ * @param path_a The first path which comes first.
+ * @param path_b The second path which comes after the first.
+ * @param buffer The buffer where the result will be written to.
+ * @param buffer_size The size of the result buffer.
+ * @return Returns the total amount of characters of the full, combined path.
+ */
+CWK_PUBLIC size_t cwk_path_join(const char *path_a, const char *path_b,
+  char *buffer, size_t buffer_size);
+
+/**
+ * @brief Joins multiple paths together.
+ *
+ * This function generates a new path by joining multiple paths together. It
+ * will remove double separators, and unlike cwk_path_get_absolute it permits
+ * the use of multiple relative paths to combine. The last path of the
+ * submitted string array must be set to NULL. The result will be written to a
+ * buffer, which might be truncated if the buffer is not large enough to hold
+ * the full path. However, the truncated result will always be
+ * null-terminated. The returned value is the amount of characters which the
+ * resulting path would take if it was not truncated (excluding the
+ * null-terminating character).
+ *
+ * @param paths An array of paths which will be joined.
+ * @param buffer The buffer where the result will be written to.
+ * @param buffer_size The size of the result buffer.
+ * @return Returns the total amount of characters of the full, combined path.
+ */
+CWK_PUBLIC size_t cwk_path_join_multiple(const char **paths, char *buffer,
+  size_t buffer_size);
+
+/**
+ * @brief Determines the root of a path.
+ *
+ * This function determines the root of a path by finding its length. The
+ * root always starts at the submitted path. If the path has no root, the
+ * length will be set to zero.
+ *
+ * @param path The path which will be inspected.
+ * @param length The output of the root length.
+ */
+CWK_PUBLIC void cwk_path_get_root(const char *path, size_t *length);
+
+/**
+ * @brief Changes the root of a path.
+ *
+ * This function changes the root of a path. It does not normalize the result.
+ * The result will be written to a buffer, which might be truncated if the
+ * buffer is not large enough to hold the full path. However, the truncated
+ * result will always be null-terminated. The returned value is the amount of
+ * characters which the resulting path would take if it was not truncated
+ * (excluding the null-terminating character).
+ *
+ * @param path The original path which will get a new root.
+ * @param new_root The new root which will be placed in the path.
+ * @param buffer The output buffer where the result is written to.
+ * @param buffer_size The size of the output buffer where the result is
+ * written to.
+ * @return Returns the total amount of characters of the new path.
+ */
+CWK_PUBLIC size_t cwk_path_change_root(const char *path, const char *new_root,
+  char *buffer, size_t buffer_size);
+
+/**
+ * @brief Determine whether the path is absolute or not.
+ *
+ * This function checks whether the path is an absolute path or not. A path is
+ * considered to be absolute if the root ends with a separator.
+ *
+ * @param path The path which will be checked.
+ * @return Returns true if the path is absolute or false otherwise.
+ */
+CWK_PUBLIC bool cwk_path_is_absolute(const char *path);
+
+/**
+ * @brief Determine whether the path is relative or not.
+ *
+ * This function checks whether the path is a relative path or not. A path is
+ * considered to be relative if the root does not end with a separator.
+ *
+ * @param path The path which will be checked.
+ * @return Returns true if the path is relative or false otherwise.
+ */
+CWK_PUBLIC bool cwk_path_is_relative(const char *path);
+
+/**
+ * @brief Gets the basename of a file path.
+ *
+ * This function gets the basename of a file path. A pointer to the beginning
+ * of the basename will be returned through the basename parameter. This
+ * pointer will be positioned on the first letter after the separator. The
+ * length of the file path will be returned through the length parameter. The
+ * length will be set to zero and the basename to NULL if there is no basename
+ * available.
+ *
+ * @param path The path which will be inspected.
+ * @param basename The output of the basename pointer.
+ * @param length The output of the length of the basename. This may be
+ * null if not required.
+ */
+CWK_PUBLIC void cwk_path_get_basename(const char *path, const char **basename,
+  size_t *length);
+
+/**
+ * @brief Changes the basename of a file path.
+ *
+ * This function changes the basename of a file path. This function will not
+ * write out more than the specified buffer can contain. However, the
+ * generated string is always null-terminated - even if not the whole path is
+ * written out. The function returns the total number of characters the
+ * complete buffer would have, even if it was not written out completely. The
+ * path may be the same memory address as the buffer.
+ *
+ * @param path The original path which will be used for the modified path.
+ * @param new_basename The new basename which will replace the old one.
+ * @param buffer The buffer where the changed path will be written to.
+ * @param buffer_size The size of the result buffer where the changed path is
+ * written to.
+ * @return Returns the size which the complete new path would have if it was
+ * not truncated.
+ */
+CWK_PUBLIC size_t cwk_path_change_basename(const char *path,
+  const char *new_basename, char *buffer, size_t buffer_size);
+
+/**
+ * @brief Gets the dirname of a file path.
+ *
+ * This function determines the dirname of a file path and returns the length
+ * up to which character is considered to be part of it. If no dirname is
+ * found, the length will be set to zero. The beginning of the dirname is
+ * always equal to the submitted path pointer.
+ *
+ * @param path The path which will be inspected.
+ * @param length The length of the dirname.
+ */
+CWK_PUBLIC void cwk_path_get_dirname(const char *path, size_t *length);
+
+/**
+ * @brief Gets the extension of a file path.
+ *
+ * This function extracts the extension portion of a file path. A pointer to
+ * the beginning of the extension will be returned through the extension
+ * parameter if an extension is found and true is returned. This pointer will
+ * be positioned on the dot. The length of the extension name will be returned
+ * through the length parameter. If no extension is found both parameters
+ * won't be touched and false will be returned.
+ *
+ * @param path The path which will be inspected.
+ * @param extension The output of the extension pointer.
+ * @param length The output of the length of the extension.
+ * @return Returns true if an extension is found or false otherwise.
+ */
+CWK_PUBLIC bool cwk_path_get_extension(const char *path, const char **extension,
+  size_t *length);
+
+/**
+ * @brief Determines whether the file path has an extension.
+ *
+ * This function determines whether the submitted file path has an extension.
+ * This will evaluate to true if the last segment of the path contains a dot.
+ *
+ * @param path The path which will be inspected.
+ * @return Returns true if the path has an extension or false otherwise.
+ */
+CWK_PUBLIC bool cwk_path_has_extension(const char *path);
+
+/**
+ * @brief Changes the extension of a file path.
+ *
+ * This function changes the extension of a file name. The function will
+ * append an extension if the basename does not have an extension, or use the
+ * extension as a basename if the path does not have a basename. This function
+ * will not write out more than the specified buffer can contain. However, the
+ * generated string is always null-terminated - even if not the whole path is
+ * written out. The function returns the total number of characters the
+ * complete buffer would have, even if it was not written out completely. The
+ * path may be the same memory address as the buffer.
+ *
+ * @param path The path which will be used to make the change.
+ * @param new_extension The extension which will be placed within the new
+ * path.
+ * @param buffer The output buffer where the result will be written to.
+ * @param buffer_size The size of the output buffer where the result will be
+ * written to.
+ * @return Returns the total size which the output would have if it was not
+ * truncated.
+ */
+CWK_PUBLIC size_t cwk_path_change_extension(const char *path,
+  const char *new_extension, char *buffer, size_t buffer_size);
+
+/**
+ * @brief Creates a normalized version of the path.
+ *
+ * This function creates a normalized version of the path within the specified
+ * buffer. This function will not write out more than the specified buffer can
+ * contain. However, the generated string is always null-terminated - even if
+ * not the whole path is written out. The returned value is the amount of
+ * characters which the resulting path would take if it was not truncated
+ * (excluding the null-terminating character). The path may be the same memory
+ * address as the buffer.
+ *
+ * The following will be true for the normalized path:
+ * 1) "../" will be resolved.
+ * 2) "./" will be removed.
+ * 3) double separators will be fixed with a single separator.
+ * 4) separator suffixes will be removed.
+ *
+ * @param path The path which will be normalized.
+ * @param buffer The buffer where the new path is written to.
+ * @param buffer_size The size of the buffer.
+ * @return The size which the complete normalized path has if it was not
+ * truncated.
+ */
+CWK_PUBLIC size_t cwk_path_normalize(const char *path, char *buffer,
+  size_t buffer_size);
+
+/**
+ * @brief Finds common portions in two paths.
+ *
+ * This function finds common portions in two paths and returns the number
+ * characters from the beginning of the base path which are equal to the other
+ * path.
+ *
+ * @param path_base The base path which will be compared with the other path.
+ * @param path_other The other path which will compared with the base path.
+ * @return Returns the number of characters which are common in the base path.
+ */
+CWK_PUBLIC size_t cwk_path_get_intersection(const char *path_base,
+  const char *path_other);
+
+/**
+ * @brief Gets the first segment of a path.
+ *
+ * This function finds the first segment of a path. The position of the
+ * segment is set to the first character after the separator, and the length
+ * counts all characters until the next separator (excluding the separator).
+ *
+ * @param path The path which will be inspected.
+ * @param segment The segment which will be extracted.
+ * @return Returns true if there is a segment or false if there is none.
+ */
+CWK_PUBLIC bool cwk_path_get_first_segment(const char *path,
+  struct cwk_segment *segment);
+
+/**
+ * @brief Gets the last segment of the path.
+ *
+ * This function gets the last segment of a path. This function may return
+ * false if the path doesn't contain any segments, in which case the submitted
+ * segment parameter is not modified. The position of the segment is set to
+ * the first character after the separator, and the length counts all
+ * characters until the end of the path (excluding the separator).
+ *
+ * @param path The path which will be inspected.
+ * @param segment The segment which will be extracted.
+ * @return Returns true if there is a segment or false if there is none.
+ */
+CWK_PUBLIC bool cwk_path_get_last_segment(const char *path,
+  struct cwk_segment *segment);
+
+/**
+ * @brief Advances to the next segment.
+ *
+ * This function advances the current segment to the next segment. If there
+ * are no more segments left, the submitted segment structure will stay
+ * unchanged and false is returned.
+ *
+ * @param segment The current segment which will be advanced to the next one.
+ * @return Returns true if another segment was found or false otherwise.
+ */
+CWK_PUBLIC bool cwk_path_get_next_segment(struct cwk_segment *segment);
+
+/**
+ * @brief Moves to the previous segment.
+ *
+ * This function moves the current segment to the previous segment. If the
+ * current segment is the first one, the submitted segment structure will stay
+ * unchanged and false is returned.
+ *
+ * @param segment The current segment which will be moved to the previous one.
+ * @return Returns true if there is a segment before this one or false
+ * otherwise.
+ */
+CWK_PUBLIC bool cwk_path_get_previous_segment(struct cwk_segment *segment);
+
+/**
+ * @brief Gets the type of the submitted path segment.
+ *
+ * This function inspects the contents of the segment and determines the type
+ * of it. Currently, there are three types CWK_NORMAL, CWK_CURRENT and
+ * CWK_BACK. A CWK_NORMAL segment is a normal folder or file entry. A
+ * CWK_CURRENT is a "./" and a CWK_BACK a "../" segment.
+ *
+ * @param segment The segment which will be inspected.
+ * @return Returns the type of the segment.
+ */
+CWK_PUBLIC enum cwk_segment_type cwk_path_get_segment_type(
+  const struct cwk_segment *segment);
+
+/**
+ * @brief Changes the content of a segment.
+ *
+ * This function overrides the content of a segment to the submitted value and
+ * outputs the whole new path to the submitted buffer. The result might
+ * require less or more space than before if the new value length differs from
+ * the original length. The output is truncated if the new path is larger than
+ * the submitted buffer size, but it is always null-terminated. The source of
+ * the segment and the submitted buffer may be the same.
+ *
+ * @param segment The segment which will be modifier.
+ * @param value The new content of the segment.
+ * @param buffer The buffer where the modified path will be written to.
+ * @param buffer_size The size of the output buffer.
+ * @return Returns the total size which would have been written if the output
+ * was not truncated.
+ */
+CWK_PUBLIC size_t cwk_path_change_segment(struct cwk_segment *segment,
+  const char *value, char *buffer, size_t buffer_size);
+
+/**
+ * @brief Checks whether the submitted pointer points to a separator.
+ *
+ * This function simply checks whether the submitted pointer points to a
+ * separator, which has to be null-terminated (but not necessarily after the
+ * separator). The function will return true if it is a separator, or false
+ * otherwise.
+ *
+ * @param str A pointer to a string.
+ * @return Returns true if it is a separator, or false otherwise.
+ */
+CWK_PUBLIC bool cwk_path_is_separator(const char *str);
+
+/**
+ * @brief Guesses the path style.
+ *
+ * This function guesses the path style based on a submitted path-string. The
+ * guessing will look at the root and the type of slashes contained in the
+ * path and return the style which is more likely used in the path.
+ *
+ * @param path The path which will be inspected.
+ * @return Returns the style which is most likely used for the path.
+ */
+CWK_PUBLIC enum cwk_path_style cwk_path_guess_style(const char *path);
+
+/**
+ * @brief Configures which path style is used.
+ *
+ * This function configures which path style is used. The following styles are
+ * currently supported.
+ *
+ * CWK_STYLE_WINDOWS: Use backslashes as a separator and volume for the root.
+ * CWK_STYLE_UNIX: Use slashes as a separator and a slash for the root.
+ *
+ * @param style The style which will be used from now on.
+ */
+CWK_PUBLIC void cwk_path_set_style(enum cwk_path_style style);
+
+/**
+ * @brief Gets the path style configuration.
+ *
+ * This function gets the style configuration which is currently used for the
+ * paths. This configuration determines how paths are parsed and generated.
+ *
+ * @return Returns the current path style configuration.
+ */
+CWK_PUBLIC enum cwk_path_style cwk_path_get_style(void);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif