mc/lib/util.h

/** \file util.h
 *  \brief Header: various utilities
 */

#ifndef MC_UTIL_H
#define MC_UTIL_H

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

#include <string.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

extern char *user_recent_timeformat;    /* time format string for recent dates */
extern char *user_old_timeformat;       /* time format string for older dates */

/* Returns its argument as a "modifiable" string. This function is
 * intended to pass strings to legacy libraries that don't know yet
 * about the "const" modifier. The return value of this function
 * MUST NOT be modified. */
extern char *str_unconst (const char *);

/* String managing functions */

extern const char *cstrcasestr (const char *haystack, const char *needle);
extern const char *cstrstr (const char *haystack, const char *needle);

void str_replace (char *s, char from, char to);
int is_printable (int c);
void msglen (const char *text, /*@out@ */ int *lines, /*@out@ */ int *columns);

/* Copy from s to d, and trim the beginning if necessary, and prepend
 * "..." in this case.  The destination string can have at most len
 * bytes, not counting trailing 0. */
char *trim (const char *s, char *d, int len);

/* Quote the filename for the purpose of inserting it into the command
 * line.  If quote_percent is 1, replace "%" with "%%" - the percent is
 * processed by the mc command line. */
char *name_quote (const char *c, int quote_percent);

/* returns a duplicate of c. */
char *fake_name_quote (const char *c, int quote_percent);

/* Remove the middle part of the string to fit given length.
 * Use "~" to show where the string was truncated.
 * Return static buffer, no need to free() it. */
const char *name_trunc (const char *txt, size_t trunc_len);

/* path_trunc() is the same as name_trunc() above but
 * it deletes possible password from path for security
 * reasons. */
const char *path_trunc (const char *path, size_t trunc_len);

/* return a static string representing size, appending "K" or "M" for
 * big sizes.
 * NOTE: uses the same static buffer as size_trunc_sep. */
const char *size_trunc (double size, gboolean use_si);

/* return a static string representing size, appending "K" or "M" for
 * big sizes. Separates every three digits by ",".
 * NOTE: uses the same static buffer as size_trunc. */
const char *size_trunc_sep (double size, gboolean use_si);

/* Print file SIZE to BUFFER, but don't exceed LEN characters,
 * not including trailing 0. BUFFER should be at least LEN+1 long.
 *
 * Units: size units (0=bytes, 1=Kbytes, 2=Mbytes, etc.) */
void size_trunc_len (char *buffer, unsigned int len, off_t size, int units, gboolean use_si);
int is_exe (mode_t mode);
const char *string_perm (mode_t mode_bits);

/* @modifies path. @returns pointer into path. */
char *strip_password (char *path, int has_prefix);

/* @returns a pointer into a static buffer. */
const char *strip_home_and_password (const char *dir);

const char *extension (const char *);
char *concat_dir_and_file (const char *dir, const char *file);
const char *unix_error_string (int error_num);
const char *skip_separators (const char *s);
const char *skip_numbers (const char *s);
char *strip_ctrl_codes (char *s);

/* Replaces "\\E" and "\\e" with "\033". Replaces "^" + [a-z] with
 * ((char) 1 + (c - 'a')). The same goes for "^" + [A-Z].
 * Returns a newly allocated string. */
char *convert_controls (const char *s);

/* overwrites passwd with '\0's and frees it. */
void wipe_password (char *passwd);

char *diff_two_paths (const char *first, const char *second);

/* Returns the basename of fname. The result is a pointer into fname. */
const char *x_basename (const char *fname);

char *load_file (const char *filename);
char *load_mc_home_file (const char *from, const char *filename, char **allocated_filename);

/* uid/gid managing */
void init_groups (void);
void destroy_groups (void);
int get_user_permissions (struct stat *buf);

void init_uid_gid_cache (void);
char *get_group (int);
char *get_owner (int);

#define MAX_I18NTIMELENGTH 20
#define MIN_I18NTIMELENGTH 10
#define STD_I18NTIMELENGTH 12

size_t i18n_checktimelength (void);
const char *file_date (time_t);

int exist_file (const char *name);

/* Check if the file exists. If not copy the default */
int check_for_default (const char *default_file, const char *file);

/* Returns a copy of *s until a \n is found and is below top */
const char *extract_line (const char *s, const char *top);

/* Matching */
enum
{
    match_file,                 /* match a filename, use easy_patterns */
    match_normal,               /* match pattern, use easy_patterns */
    match_regex                 /* match pattern, force using regex */
};

extern int easy_patterns;

/* Error pipes */
void open_error_pipe (void);
void check_error_pipe (void);
int close_error_pipe (int error, const char *text);

/* Process spawning */
int my_system (int flags, const char *shell, const char *command);
void save_stop_handler (void);
extern struct sigaction startup_handler;

/* Tilde expansion */
char *tilde_expand (const char *);

/* Pathname canonicalization */
typedef enum
{
    CANON_PATH_JOINSLASHES = 1L << 0,   /* Multiple `/'s are collapsed to a single `/'. */
    CANON_PATH_REMSLASHDOTS = 1L << 1,  /* Leading `./'s, `/'s and trailing `/.'s are removed. */
    CANON_PATH_REMDOUBLEDOTS = 1L << 3, /* Non-leading `../'s and trailing `..'s are handled by removing */
    CANON_PATH_GUARDUNC = 1L << 4,      /* Detect and preserve UNC paths: //server/... */
    CANON_PATH_ALL = CANON_PATH_JOINSLASHES
        | CANON_PATH_REMSLASHDOTS | CANON_PATH_REMDOUBLEDOTS | CANON_PATH_GUARDUNC
} CANON_PATH_FLAGS;
void custom_canonicalize_pathname (char *, CANON_PATH_FLAGS);
void canonicalize_pathname (char *);

/* Misc Unix functions */
int my_mkdir (const char *s, mode_t mode);
int my_rmdir (const char *s);

/* Rotating dash routines */
void use_dash (int flag);       /* Disable/Enable rotate_dash routines */
void rotate_dash (void);

/* Creating temporary files safely */
const char *mc_tmpdir (void);
int mc_mkstemps (char **pname, const char *prefix, const char *suffix);

#ifndef PATH_MAX
#ifdef _POSIX_VERSION
#define PATH_MAX _POSIX_PATH_MAX
#else
#ifdef MAXPATHLEN
#define PATH_MAX MAXPATHLEN
#else
#define PATH_MAX 1024
#endif
#endif
#endif

#ifndef MAXSYMLINKS
#define MAXSYMLINKS 32
#endif

#ifdef HAVE_REALPATH
#define mc_realpath realpath
#else
char *mc_realpath (const char *path, char *resolved_path);
#endif

enum compression_type
{
    COMPRESSION_NONE,
    COMPRESSION_GZIP,
    COMPRESSION_BZIP,
    COMPRESSION_BZIP2,
    COMPRESSION_LZMA,
    COMPRESSION_XZ
};

/* Looks for ``magic'' bytes at the start of the VFS file to guess the
 * compression type. Side effect: modifies the file position. */
enum compression_type get_compression_type (int fd, const char *);
const char *decompress_extension (int type);

/* Hook functions */

typedef struct hook
{
    void (*hook_fn) (void *);
    void *hook_data;
    struct hook *next;
} Hook;

void add_hook (Hook ** hook_list, void (*hook_fn) (void *), void *data);
void execute_hooks (Hook * hook_list);
void delete_hook (Hook ** hook_list, void (*hook_fn) (void *));
int hook_present (Hook * hook_list, void (*hook_fn) (void *));

GList *list_append_unique (GList * list, char *text);

/* Position saving and restoring */
#define MAX_SAVED_BOOKMARKS 10
/* Load position for the given filename */
void load_file_position (const char *filename, long *line, long *column, off_t * offset,
                         GArray **bookmarks);
/* Save position for the given filename */
void save_file_position (const char *filename, long line, long column, off_t offset,
                         GArray *bookmarks);


/* OS specific defines */
#define PATH_SEP '/'
#define PATH_SEP_STR "/"
#define PATH_ENV_SEP ':'
#define TMPDIR_DEFAULT "/tmp"
#define SCRIPT_SUFFIX ""
#define get_default_editor() "vi"
#define OS_SORT_CASE_SENSITIVE_DEFAULT 1
#define STRCOMP strcmp
#define STRNCOMP strncmp
#define MC_ARCH_FLAGS 0

/* taken from regex.c: */
/* Jim Meyering writes:

   "... Some ctype macros are valid only for character codes that
   isascii says are ASCII (SGI's IRIX-4.0.5 is one such system --when
   using /bin/cc or gcc but without giving an ansi option).  So, all
   ctype uses should be through macros like ISPRINT...  If
   STDC_HEADERS is defined, then autoconf has verified that the ctype
   macros don't need to be guarded with references to isascii. ...
   Defining isascii to 1 should let any compiler worth its salt
   eliminate the && through constant folding."  */

#if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
#define ISASCII(c) 1
#else
#define ISASCII(c) isascii(c)
#endif

/* usage: str_cmp ("foo", !=, "bar") */
#define str_cmp(a,rel,b) (strcmp ((a), (b)) rel 0)

/* if ch is in [A-Za-z], returns the corresponding control character,
 * else returns the argument. */
extern int ascii_alpha_to_cntrl (int ch);

#undef Q_
const char *Q_ (const char *s);

#define str_dup_range(s_start, s_bound) (g_strndup(s_start, s_bound - s_start))

/*
 * 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;

    assert (dest <= src);

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

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

gboolean mc_util_make_backup_if_possible (const char *, const char *);
gboolean mc_util_restore_from_backup_if_possible (const char *, const char *);
gboolean mc_util_unlink_backup_if_possible (const char *, const char *);

char *guess_message_value (void);

#define MC_PTR_FREE(ptr) do { g_free (ptr); (ptr) = NULL; } while (0)

#endif /* MC_UTIL_H */