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Dynamic Strings And String Helpers

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Dynamic Strings And String Helpers

Provides string helper structures/functions (roughly equivalent to std::string).

.. code:: cpp

#include <util/dstr.h>

Dynamic String Structure (struct dstr)

.. struct:: dstr .. member:: char *dstr.array .. member:: size_t dstr.len .. member:: size_t dstr.capacity

General String Helper Functions

.. function:: int astrcmpi(const char *str1, const char *str2)

Case insensitive string comparison function.


.. function:: int wstrcmpi(const wchar_t *str1, const wchar_t *str2)

Case insensitive wide string comparison function.


.. function:: int astrcmp_n(const char *str1, const char *str2, size_t n)

String comparison function for a specific number of characters.


.. function:: int wstrcmp_n(const wchar_t *str1, const wchar_t *str2, size_t n)

Wide string comparison function for a specific number of characters.


.. function:: int astrcmpi_n(const char *str1, const char *str2, size_t n)

Case insensitive string comparison function for a specific number of characters.


.. function:: int wstrcmpi_n(const wchar_t *str1, const wchar_t *str2, size_t n)

Case insensitive wide string comparison function for a specific number of characters.


.. function:: char *astrstri(const char *str, const char *find)

Case insensitive version of strstr.


.. function:: wchar_t *wstrstri(const wchar_t *str, const wchar_t *find)

Case insensitive version of wcsstr.


.. function:: char *strdepad(char *str)

Removes padding characters (tab, space, CR, LF) from the front and end of a string.


.. function:: wchar_t *wcsdepad(wchar_t *str)

Removes padding characters (tab, space, CR, LF) from the front and end of a wide string.


.. function:: char **strlist_split(const char *str, char split_ch, bool include_empty)

Splits a string in to a list of multiple sub-strings, terminated by NULL. If split_ch does not exist in the string, the first sub-string will be the same as str. Free with :c:func:strlist_free().

:param str: The string to be split :param split_ch: The delimiter :param include_empty: If true, empty strings caused by having the split_ch right next to another will be included in the list. If false, they won't be included.

Sample usage:

.. code:: cpp

  char **words = strlist_split("OBS    Studio", ' ', false);
  int count = 0;

  for (char **word = words; *word; ++word) {
          count++;
          blog(LOG_DEBUG, "%s", *word);
  }

  strlist_free(words);
  // count == 2

.. function:: void strlist_free(char **strlist)

Frees a string list created with :c:func:strlist_split().


Dynamic String Functions

.. function:: void dstr_init(struct dstr *dst)

Initializes a dynamic string variable (just zeroes the variable).

:param dst: Dynamic string to initialize


.. function:: void dstr_init_move(struct dstr *dst, struct dstr *src)

Moves a src to dst without copying data and zeroes src.

:param dst: Destination :param src: Source


.. function:: void dstr_init_move_array(struct dstr *dst, char *str)

Sets a bmalloc-allocated string as the dynamic string without copying/reallocating.

:param dst: Dynamic string to initialize :param str: bmalloc-allocated string


.. function:: void dstr_init_copy(struct dstr *dst, const char *src)

Initializes a dynamic string with a copy of a string

:param dst: Dynamic string to initialize :param src: String to copy


.. function:: void dstr_init_copy_dstr(struct dstr *dst, const struct dstr *src)

Initializes a dynamic string with a copy of another dynamic string

:param dst: Dynamic string to initialize :param src: Dynamic string to copy


.. function:: void dstr_free(struct dstr *dst)

Frees a dynamic string.

:param dst: Dynamic string


.. function:: void dstr_copy(struct dstr *dst, const char *array)

Copies a string.

:param dst: Dynamic string :param array: String to copy


.. function:: void dstr_copy_dstr(struct dstr *dst, const struct dstr *src)

Copies another dynamic string.

:param dst: Dynamic string :param src: Dynamic string to copy


.. function:: void dstr_ncopy(struct dstr *dst, const char *array, const size_t len)

Copies a specific number of characters from a string.

:param dst: Dynamic string :param array: String to copy :param len: Number of characters to copy


.. function:: void dstr_ncopy_dstr(struct dstr *dst, const struct dstr *src, const size_t len)

Copies a specific number of characters from another dynamic string.

:param dst: Dynamic string :param src: Dynamic string to copy :param len: Number of characters to copy


.. function:: void dstr_resize(struct dstr *dst, const size_t num)

Sets the size of the dynamic string. If the new size is bigger than current size, zeroes the new characters.

:param dst: Dynamic string :param num: New size


.. function:: void dstr_reserve(struct dstr *dst, const size_t num)

Reserves a specific number of characters in the buffer (but does not change the size). Does not work if the value is smaller than the current reserve size.

:param dst: Dynamic string :param num: New reserve size


.. function:: bool dstr_is_empty(const struct dstr *str)

Returns whether the dynamic string is empty.

:param str: Dynamic string :return: true if empty, false otherwise


.. function:: void dstr_cat(struct dstr *dst, const char *array)

Concatenates a dynamic string.

:param dst: Dynamic string :param array: String to concatenate with


.. function:: void dstr_cat_dstr(struct dstr *dst, const struct dstr *str)

Concatenates a dynamic string with another dynamic string.

:param dst: Dynamic string to concatenate to :param str: Dynamic string to concatenate with


.. function:: void dstr_cat_ch(struct dstr *dst, char ch)

Concatenates a dynamic string with a single character.

:param dst: Dynamic string to concatenate to :param ch: Character to concatenate


.. function:: void dstr_ncat(struct dstr *dst, const char *array, const size_t len)

Concatenates a dynamic string with a specific number of characters from a string.

:param dst: Dynamic string to concatenate to :param array: String to concatenate with :param len: Number of characters to concatenate with


.. function:: void dstr_ncat_dstr(struct dstr *dst, const struct dstr *str, const size_t len)

Concatenates a dynamic string with a specific number of characters from another dynamic string.

:param dst: Dynamic string to concatenate to :param str: Dynamic string to concatenate with :param len: Number of characters to concatenate with


.. function:: void dstr_insert(struct dstr *dst, const size_t idx, const char *array)

Inserts a string in to a dynamic string at a specific index.

:param dst: Dynamic string to insert in to :param idx: Character index to insert at :param array: String to insert


.. function:: void dstr_insert_dstr(struct dstr *dst, const size_t idx, const struct dstr *str)

Inserts another dynamic string in to a dynamic string at a specific index.

:param dst: Dynamic string to insert in to :param idx: Character index to insert at :param str: Dynamic string to insert


.. function:: void dstr_insert_ch(struct dstr *dst, const size_t idx, const char ch)

Inserts a character in to a dynamic string at a specific index.

:param dst: Dynamic string to insert in to :param idx: Character index to insert at :param ch: Character to insert


.. function:: void dstr_remove(struct dstr *dst, const size_t idx, const size_t count)

Removes a specific number of characters starting from a specific index.

:param dst: Dynamic string :param idx: Index to start removing characters at :param count: Number of characters to remove


.. function:: void dstr_printf(struct dstr *dst, const char *format, ...) void dstr_vprintf(struct dstr *dst, const char *format, va_list args)

Sets a dynamic string to a formatted string.

:param dst: Dynamic string :param format: Format string


.. function:: void dstr_catf(struct dstr *dst, const char *format, ...) void dstr_vcatf(struct dstr *dst, const char *format, va_list args)

Concatenates a dynamic string with a formatted string.

:param dst: Dynamic string :param format: Format string


.. function:: const char *dstr_find_i(const struct dstr *str, const char *find)

Finds a string within a dynamic string, case insensitive.

:param str: Dynamic string :param find: String to find :return: Pointer to the first occurrence, or NULL if not found


.. function:: const char *dstr_find(const struct dstr *str, const char *find)

Finds a string within a dynamic string.

:param str: Dynamic string :param find: String to find :return: Pointer to the first occurrence, or NULL if not found


.. function:: void dstr_replace(struct dstr *str, const char *find, const char *replace)

Replaces all occurrences of find with replace.

:param str: Dynamic string :param find: String to find :param replace: Replacement string


.. function:: int dstr_cmp(const struct dstr *str1, const char *str2)

Compares with a string.

:param str1: Dynamic string :param str2: String to compare :return: 0 if equal, nonzero otherwise


.. function:: int dstr_cmpi(const struct dstr *str1, const char *str2)

Compares with a string, case-insensitive.

:param str1: Dynamic string :param str2: String to compare :return: 0 if equal, nonzero otherwise


.. function:: int dstr_ncmp(const struct dstr *str1, const char *str2, const size_t n)

Compares a specific number of characters.

:param str1: Dynamic string :param str2: String to compare :param n: Number of characters to compare :return: 0 if equal, nonzero otherwise


.. function:: int dstr_ncmpi(const struct dstr *str1, const char *str2, const size_t n)

Compares a specific number of characters, case-insensitive.

:param str1: Dynamic string :param str2: String to compare :param n: Number of characters to compare :return: 0 if equal, nonzero otherwise


.. function:: void dstr_depad(struct dstr *dst)

Removes all padding characters (tabs, spaces, CR, LF) from the front and ends of a dynamic string.

:param dst: Dynamic string


.. function:: void dstr_left(struct dstr *dst, const struct dstr *str, const size_t pos)

Copies a certain number of characters from the left side of one dynamic string in to another.

:param dst: Destination :param str: Source :param pos: Number of characters


.. function:: void dstr_mid(struct dstr *dst, const struct dstr *str, const size_t start, const size_t count)

Copies a certain number of characters from the middle of one dynamic string in to another.

:param dst: Destination :param str: Source :param start: Starting index within str :param count: Number of characters to copy


.. function:: void dstr_right(struct dstr *dst, const struct dstr *str, const size_t pos)

Copies a certain number of characters from the right of one dynamic string in to another.

:param dst: Destination :param str: Source :param pos: Index of str to copy from


.. function:: char dstr_end(const struct dstr *str)

:param str: Dynamic string :return: The last character of a dynamic string


.. function:: void dstr_from_wcs(struct dstr *dst, const wchar_t *wstr)

Copies a wide string in to a dynamic string and converts it to UTF-8.

:param dst: Dynamic string :param wstr: Wide string


.. function:: wchar_t *dstr_to_wcs(const struct dstr *str)

Converts a dynamic array to a wide string. Free with :c:func:bfree().

:param str: Dynamic string :return: Wide string allocation. Free with :c:func:bfree()


.. function:: void dstr_to_upper(struct dstr *str)

Converts all characters within a dynamic array to uppercase.

:param str: Dynamic string


.. function:: void dstr_to_lower(struct dstr *str)

Converts all characters within a dynamic array to lowercase.

:param str: Dynamic string