mc/lib/strutil.h

#ifndef MC_STRUTIL_H
#define MC_STRUTIL_H

#include "lib/global.h"         /* include glib.h */

#include <sys/types.h>
#include <string.h>
#ifdef HAVE_ASSERT_H
#include <assert.h>             /* assert() */
#endif

/* Header file for strutil.c, strutilascii.c, strutil8bit.c, strutilutf8.c.
 * There are two sort of functions:
 * 1. functions for working with growing strings and conversion strings between
 *    different encodings.
 *    (implemented directly in strutil.c)
 * 2. functions, that hide differences between encodings derived from ASCII.
 *    (implemented separately in strutilascii.c, strutil8bit.c, strutilutf8.c)
 * documentation is made for UTF-8 version of functions.
 */

/* invalid strings
 * function, that works with invalid strings are marked with "I" 
 * in documentation
 * invalid bytes of string are handled as one byte characters with width 1, they
 * are displayed as questionmarks, I-maked comparing functions try to keep 
 * the original value of these bytes.
 */

/* combining characters
 * displaynig: all handled as zero with characters, expect combing character 
 * at the begin of string, this character has with one (space add before), 
 * so str_term_width is not good for computing width of singles characters 
 * (never return zero, expect emtpy string)
 * for compatibility are strings composed before displaynig
 * comparing: comparing decompose all string before comparing, n-compare 
 * functions do not work as is usual, because same strings do not have to be 
 * same length in UTF-8. So they return 0 if one string is prefix of the other 
 * one. 
 * str_prefix is used to determine, how many characters from one string are 
 * prefix in second string. However, str_prefix return number of characters in
 * decompose form. (used in do_search (screen.c))
 */

/*** typedefs(not structures) and defined constants **********************************************/

#define IS_FIT(x) ((x) & 0x0010)
#define MAKE_FIT(x) ((x) | 0x0010)
#define HIDE_FIT(x) ((x) & 0x000f)

#define INVALID_CONV ((GIConv) (-1))

/*** enums ***************************************************************************************/

/* results of conversion function
 */
typedef enum
{
    /* success means, that convertion has been finished successully
     */
    ESTR_SUCCESS = 0,
    /* problem means, that not every characters was successfully converted (They are
     * replaced with questionmark). So is impossible convert string back. 
     */
    ESTR_PROBLEM = 1,
    /* failure means, that conversion is not possible (example: wrong encoding 
     * of input string)
     */
    ESTR_FAILURE = 2
} estr_t;

/* alignment strings on terminal
 */
typedef enum
{
    J_LEFT = 0x01,
    J_RIGHT = 0x02,
    J_CENTER = 0x03,
    /* if there is enough space for string on terminal,
     * string is centered otherwise is aligned to left */
    J_CENTER_LEFT = 0x04,
    /* fit alignment, if string is to long, is truncated with '~' */
    J_LEFT_FIT = 0x11,
    J_RIGHT_FIT = 0x12,
    J_CENTER_FIT = 0x13,
    J_CENTER_LEFT_FIT = 0x14
} align_crt_t;

/*** structures declarations (and typedefs of structures)*****************************************/

/* all functions in str_class must be defined for every encoding */
struct str_class
{
    gchar *(*conv_gerror_message) (GError * error, const char *def_msg);
      /*I*/ estr_t (*vfs_convert_to) (GIConv coder, const char *string, int size, GString * buffer);
      /*I*/ void (*insert_replace_char) (GString * buffer);
    int (*is_valid_string) (const char *);
      /*I*/ int (*is_valid_char) (const char *, size_t);
      /*I*/ void (*cnext_char) (const char **);
    void (*cprev_char) (const char **);
    void (*cnext_char_safe) (const char **);
      /*I*/ void (*cprev_char_safe) (const char **);
      /*I*/ int (*cnext_noncomb_char) (const char **text);
      /*I*/ int (*cprev_noncomb_char) (const char **text, const char *begin);
      /*I*/ int (*char_isspace) (const char *);
      /*I*/ int (*char_ispunct) (const char *);
      /*I*/ int (*char_isalnum) (const char *);
      /*I*/ int (*char_isdigit) (const char *);
      /*I*/ int (*char_isprint) (const char *);
      /*I*/ gboolean (*char_iscombiningmark) (const char *);
      /*I*/ int (*length) (const char *);
      /*I*/ int (*length2) (const char *, int);
      /*I*/ int (*length_noncomb) (const char *);
      /*I*/ int (*char_toupper) (const char *, char **, size_t *);
    int (*char_tolower) (const char *, char **, size_t *);
    void (*fix_string) (char *);
      /*I*/ const char *(*term_form) (const char *);
      /*I*/ const char *(*fit_to_term) (const char *, int, align_crt_t);
      /*I*/ const char *(*term_trim) (const char *text, int width);
      /*I*/ const char *(*term_substring) (const char *, int, int);
      /*I*/ int (*term_width1) (const char *);
      /*I*/ int (*term_width2) (const char *, size_t);
      /*I*/ int (*term_char_width) (const char *);
      /*I*/ const char *(*trunc) (const char *, int);
      /*I*/ int (*offset_to_pos) (const char *, size_t);
      /*I*/ int (*column_to_pos) (const char *, size_t);
      /*I*/ char *(*create_search_needle) (const char *, int);
    void (*release_search_needle) (char *, int);
    const char *(*search_first) (const char *, const char *, int);
    const char *(*search_last) (const char *, const char *, int);
    int (*compare) (const char *, const char *);
      /*I*/ int (*ncompare) (const char *, const char *);
      /*I*/ int (*casecmp) (const char *, const char *);
      /*I*/ int (*ncasecmp) (const char *, const char *);
      /*I*/ int (*prefix) (const char *, const char *);
      /*I*/ int (*caseprefix) (const char *, const char *);
      /*I*/ char *(*create_key) (const char *text, int case_sen);
      /*I*/ char *(*create_key_for_filename) (const char *text, int case_sen);
      /*I*/ int (*key_collate) (const char *t1, const char *t2, int case_sen);
      /*I*/ void (*release_key) (char *key, int case_sen);
  /*I*/};

/*** global variables defined in .c file *********************************************************/

/* standard convertors */
extern GIConv str_cnv_to_term;
extern GIConv str_cnv_from_term;
/* from terminal encoding to terminal encoding */
extern GIConv str_cnv_not_convert;

/*** declarations of public functions ************************************************************/

struct str_class str_utf8_init (void);
struct str_class str_8bit_init (void);
struct str_class str_ascii_init (void);

/* create convertor from "from_enc" to terminal encoding
 * if "from_enc" is not supported return INVALID_CONV 
 */
GIConv str_crt_conv_from (const char *);

/* create convertor from terminal encoding to "to_enc"
 * if "to_enc" is not supported return INVALID_CONV 
 */
GIConv str_crt_conv_to (const char *);

/* close convertor, do not close str_cnv_to_term, str_cnv_from_term, 
 * str_cnv_not_convert 
 */
void str_close_conv (GIConv);

/* return on of not used buffers (.used == 0) or create new
 * returned buffer has set .used to 1
 */

/* convert string using coder, result of conversion is appended at end of buffer
 * return ESTR_SUCCESS if there was no problem.
 * otherwise return  ESTR_PROBLEM or ESTR_FAILURE
 */
estr_t str_convert (GIConv, const char *, GString *);
estr_t str_nconvert (GIConv, const char *, int, GString *);

/* convert GError message (which in UTF-8) to terminal charset
 * def_char is used if result of error->str conversion if ESTR_FAILURE
 * return new allocated null-terminated string, which is need to be freed
 * I
 */
gchar *str_conv_gerror_message (GError * error, const char *def_msg);

/* return only ESTR_SUCCESS or ESTR_FAILURE, because vfs must be able to convert
 * result to original string. (so no replace with questionmark)
 * if coder is str_cnv_from_term or str_cnv_not_convert, string is only copied,
 * so is possible to show file, that is not valid in terminal encoding
 */
estr_t str_vfs_convert_from (GIConv, const char *, GString *);

/* if coder is str_cnv_to_term or str_cnv_not_convert, string is only copied,
 * does replace with questionmark 
 * I
 */
estr_t str_vfs_convert_to (GIConv, const char *, int, GString *);

/* printf functin for str_buffer, append result of printf at the end of buffer
 */
void str_printf (GString *, const char *, ...);

/* add standard replacement character in terminal encoding
 */
void str_insert_replace_char (GString *);

/* init strings and set terminal encoding,
 * if is termenc NULL, detect terminal encoding
 * create all str_cnv_* and set functions for terminal encoding
 */
void str_init_strings (const char *termenc);

/* free all str_buffer and all str_cnv_*
 */
void str_uninit_strings (void);

/* try convert characters in ch to output using conv
 * ch_size is size of ch, can by (size_t)(-1) (-1 only for ASCII 
 *     compatible encoding, for other must be set)
 * return ESTR_SUCCESS if conversion was successfully,
 * ESTR_PROBLEM if ch contains only part of characters,
 * ESTR_FAILURE if conversion is not possible
 */
estr_t str_translate_char (GIConv conv, const char *ch, size_t ch_size,
                           char *output, size_t out_size);

/* test, if text is valid in terminal encoding
 * I
 */
int str_is_valid_string (const char *text);

/* test, if first char of ch is valid
 * size, how many bytes characters occupied, could be (size_t)(-1)
 * return 1 if it is valid, -1 if it is invalid or -2 if it is only part of 
 * multibyte character 
 * I
 */
int str_is_valid_char (const char *ch, size_t size);

/* return next characters after text, do not call on the end of string
 */
char *str_get_next_char (char *text);
const char *str_cget_next_char (const char *text);

/* return previous characters before text, do not call on the start of strings
 */
char *str_get_prev_char (char *text);
const char *str_cget_prev_char (const char *text);

/* set text to next characters, do not call on the end of string
 */
void str_next_char (char **text);
void str_cnext_char (const char **text);

/* set text to previous characters, do not call on the start of strings
 */
void str_prev_char (char **text);
void str_cprev_char (const char **text);

/* return next characters after text, do not call on the end of string
 * works with invalid string 
 * I
 */
char *str_get_next_char_safe (char *text);
const char *str_cget_next_char_safe (const char *text);

/* return previous characters before text, do not call on the start of strings
 * works with invalid string 
 * I
 */
char *str_get_prev_char_safe (char *text);
const char *str_cget_prev_char_safe (const char *text);

/* set text to next characters, do not call on the end of string
 * works with invalid string 
 * I
 */
void str_next_char_safe (char **text);
void str_cnext_char_safe (const char **text);

/* set text to previous characters, do not call on the start of strings
 * works with invalid string 
 * I
 */
void str_prev_char_safe (char **text);
void str_cprev_char_safe (const char **text);

/* set text to next noncombining characters, check the end of text
 * return how many characters was skipped
 * works with invalid string 
 * I
 */
int str_next_noncomb_char (char **text);
int str_cnext_noncomb_char (const char **text);

/* set text to previous noncombining characters, search stop at begin 
 * return how many characters was skipped
 * works with invalid string 
 * I
 */
int str_prev_noncomb_char (char **text, const char *begin);
int str_cprev_noncomb_char (const char **text, const char *begin);

/* if first characters in ch is space, tabulator  or new lines
 * I
 */
int str_isspace (const char *ch);

/* if first characters in ch is punctuation or symbol
 * I
 */
int str_ispunct (const char *ch);

/* if first characters in ch is alphanum
 * I
 */
int str_isalnum (const char *ch);

/* if first characters in ch is digit
 * I
 */
int str_isdigit (const char *ch);

/* if first characters in ch is printable
 * I
 */
int str_isprint (const char *ch);

/* if first characters in ch is a combining mark (only in utf-8)
 * combining makrs are assumed to be zero width 
 * I
 */
gboolean str_iscombiningmark (const char *ch);

/* write lower from of fisrt characters in ch into out
 * decrase remain by size of returned characters
 * if out is not big enough, do nothing
 */
int str_toupper (const char *ch, char **out, size_t * remain);

/* write upper from of fisrt characters in ch into out
 * decrase remain by size of returned characters
 * if out is not big enough, do nothing
 */
int str_tolower (const char *ch, char **out, size_t * remain);

/* return length of text in characters
 * I
 */
int str_length (const char *text);

/* return length of text in characters, limit to size
 * I
 */
int str_length2 (const char *text, int size);

/* return length of one char
 * I
 */
int str_length_char (const char *);

/* return length of text in characters, count only noncombining characters
 * I
 */
int str_length_noncomb (const char *text);

/* replace all invalid characters in text with questionmark
 * after return, text is valid string in terminal encoding
 * I
 */
void str_fix_string (char *text);

/* replace all invalid characters in text with questionmark
 * replace all unprintable characters with '.'
 * return static allocated string, "text" is not changed
 * returned string do not need to be freed
 * I
 */
const char *str_term_form (const char *text);

/* like str_term_form, but text can be alignment to width
 * alignment is specified in just_mode (J_LEFT, J_LEFT_FIT, ...)
 * result is completed with spaces to width
 * I
 */
const char *str_fit_to_term (const char *text, int width, align_crt_t just_mode);

/* like str_term_form, but when text is wider than width, three dots are
 * inserted at begin and result is completed with suffix of text
 * no additional spaces are inserted
 * I
 */
const char *str_term_trim (const char *text, int width);


/* like str_term_form, but return only specified substring
 * start - column (position) on terminal, where substring begin
 * result is completed with spaces to width
 * I
 */
const char *str_term_substring (const char *text, int start, int width);

/* return width, that will be text occupied on terminal
 * I
 */
int str_term_width1 (const char *text);

/* return width, that will be text occupied on terminal
 * text is limited by length in characters
 * I
 */
int str_term_width2 (const char *text, size_t length);

/* return width, that will be character occupied on terminal
 * combining characters are always zero width
 * I
 */
int str_term_char_width (const char *text);

/* convert position in characters to position in bytes 
 * I
 */
int str_offset_to_pos (const char *text, size_t length);

/* convert position on terminal to position in characters
 * I
 */
int str_column_to_pos (const char *text, size_t pos);

/* like str_fit_to_term width just_mode = J_LEFT_FIT, 
 * but do not insert additional spaces
 * I
 */
const char *str_trunc (const char *text, int width);

/* create needle, that will be searched in str_search_fist/last,
 * so needle can be reused
 * in UTF-8 return normalized form of needle
 */
char *str_create_search_needle (const char *needle, int case_sen);

/* free needle returned by str_create_search_needle
 */
void str_release_search_needle (char *needle, int case_sen);

/* search for first occurrence of search in text
 */
const char *str_search_first (const char *text, const char *needle, int case_sen);

/* search for last occurrence of search in text
 */
const char *str_search_last (const char *text, const char *needle, int case_sen);

/* case sensitive compare two strings
 * I
 */
int str_compare (const char *t1, const char *t2);

/* case sensitive compare two strings
 * if one string is prefix of the other string, return 0
 * I
 */
int str_ncompare (const char *t1, const char *t2);

/* case insensitive compare two strings
 * I
 */
int str_casecmp (const char *t1, const char *t2);

/* case insensitive compare two strings
 * if one string is prefix of the other string, return 0
 * I
 */
int str_ncasecmp (const char *t1, const char *t2);

/* return, how many bytes are are same from start in text and prefix
 * both strings are decomposed befor comapring and return value is counted
 * in decomposed form, too. caling with prefix, prefix, you get size in bytes
 * of prefix in decomposed form,
 * I
 */
int str_prefix (const char *text, const char *prefix);

/* case insensitive version of str_prefix
 * I
 */
int str_caseprefix (const char *text, const char *prefix);

/* create a key that is used by str_key_collate
 * I
 */
char *str_create_key (const char *text, int case_sen);

/* create a key that is used by str_key_collate
 * should aware dot '.' in text
 * I
 */
char *str_create_key_for_filename (const char *text, int case_sen);

/* compare two string using LC_COLLATE, if is possible
 * if case_sen is set, comparing is case sensitive,
 * case_sen must be same for str_create_key, str_key_collate and str_release_key
 * I
 */
int str_key_collate (const char *t1, const char *t2, int case_sen);

/* release_key created by str_create_key, only rigth way to release key
 * I
 */
void str_release_key (char *key, int case_sen);

/* return TRUE if codeset_name is utf8 or utf-8
 * I
 */
gboolean str_isutf8 (const char *codeset_name);

const char *str_detect_termencoding (void);

int str_verscmp (const char *s1, const char *s2);

/* return how many lines and columns will text occupy on terminal
 */
void str_msg_term_size (const char *text, int *lines, int *columns);

/**
 skip first <skip_count>  needle's in haystack and returns pointer to
 <skip_count+1> needle (or NULL if not found).
 */
char *strrstr_skip_count (const char *haystack, const char *needle, size_t skip_count);

/*** inline functions ****************************************************************************/

static inline void
str_replace (char *s, char from, char to)
{
    for (; *s != '\0'; s++)
    {
        if (*s == from)
            *s = to;
    }
}

/*
 * strcpy is unsafe on overlapping memory areas, so define memmove-alike
 * string function.
 * Have sense only when:
 *  * dest <= src
 *   AND
 *  * dest and str are pointers to one object (as Roland Illig pointed).
 *
 * We can't use str*cpy funs here:
 * http://kerneltrap.org/mailarchive/openbsd-misc/2008/5/27/1951294
 */
static inline char *
str_move (char *dest, const char *src)
{
    size_t n;

#ifdef HAVE_ASSERT_H
    assert (dest <= src);
#endif

    n = strlen (src) + 1;       /* + '\0' */

    return (char *) memmove (dest, src, n);
}

#endif /* MC_STRUTIL_H */