X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fbackupfile.c;h=7f4da17fcadc96cc973eaa336d235257571e7900;hb=c6cb26ec2993800dda1b95c213fc4539acd4fa51;hp=2ca512532d2ce9313dc4b2fd8a7d063e06e20887;hpb=c6b00bfe22ebaf71ad2dc53cd74c3a192fc7a744;p=gnulib.git diff --git a/lib/backupfile.c b/lib/backupfile.c index 2ca512532..7f4da17fc 100644 --- a/lib/backupfile.c +++ b/lib/backupfile.c @@ -1,5 +1,5 @@ /* backupfile.c -- make Emacs style backup file names - Copyright (C) 1990 Free Software Foundation, Inc. + Copyright (C) 1990-1997, 1998, 1999 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -12,100 +12,103 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software Foundation, - Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + along with this program; see the file COPYING. + If not, write to the Free Software Foundation, + 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ -/* David MacKenzie . +/* Written by David MacKenzie . Some algorithms adapted from GNU Emacs. */ -#ifdef HAVE_CONFIG_H +#if HAVE_CONFIG_H # include #endif +#include +#include + #include -#include #include -#include "backupfile.h" -#ifdef HAVE_STRING_H +#if HAVE_STRING_H # include #else # include #endif -#ifdef HAVE_DIRENT_H +#if HAVE_DIRENT_H # include -# define NLENGTH(direct) (strlen((direct)->d_name)) -#else /* not HAVE_DIRENT_H */ +# define NLENGTH(direct) strlen ((direct)->d_name) +#else # define dirent direct -# define NLENGTH(direct) ((direct)->d_namlen) -# ifdef HAVE_SYS_NDIR_H +# define NLENGTH(direct) ((size_t) (direct)->d_namlen) +# if HAVE_SYS_NDIR_H # include -# endif /* HAVE_SYS_NDIR_H */ -# ifdef HAVE_SYS_DIR_H +# endif +# if HAVE_SYS_DIR_H # include -# endif /* HAVE_SYS_DIR_H */ -# ifdef HAVE_NDIR_H +# endif +# if HAVE_NDIR_H # include -# endif /* HAVE_NDIR_H */ -#endif /* HAVE_DIRENT_H */ +# endif +#endif -#ifdef CLOSEDIR_VOID +#if CLOSEDIR_VOID /* Fake a return value. */ # define CLOSEDIR(d) (closedir (d), 0) #else # define CLOSEDIR(d) closedir (d) #endif -#ifdef STDC_HEADERS +#if STDC_HEADERS # include #else char *malloc (); #endif -#if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII)) -# define IN_CTYPE_DOMAIN(c) 1 +#ifndef HAVE_DECL_GETENV +char *getenv (); +#endif + +char *base_name PARAMS ((char const *)); + +#if HAVE_DIRENT_H || HAVE_NDIR_H || HAVE_SYS_DIR_H || HAVE_SYS_NDIR_H +# define HAVE_DIR 1 #else -# define IN_CTYPE_DOMAIN(c) isascii(c) +# define HAVE_DIR 0 #endif -#define ISDIGIT_LOCALE(c) (IN_CTYPE_DOMAIN (c) && isdigit (c)) +#if HAVE_LIMITS_H +# include +#endif +#ifndef CHAR_BIT +# define CHAR_BIT 8 +#endif +/* Upper bound on the string length of an integer converted to string. + 302 / 1000 is ceil (log10 (2.0)). Subtract 1 for the sign bit; + add 1 for integer division truncation; add 1 more for a minus sign. */ +#define INT_STRLEN_BOUND(t) ((sizeof (t) * CHAR_BIT - 1) * 302 / 1000 + 2) -/* ISDIGIT differs from ISDIGIT_LOCALE, as follows: +/* ISDIGIT differs from isdigit, as follows: - Its arg may be any int or unsigned int; it need not be an unsigned char. - It's guaranteed to evaluate its argument exactly once. - It's typically faster. Posix 1003.2-1992 section 2.5.2.1 page 50 lines 1556-1558 says that - only '0' through '9' are digits. Prefer ISDIGIT to ISDIGIT_LOCALE unless + only '0' through '9' are digits. Prefer ISDIGIT to isdigit unless it's important to use the locale's definition of `digit' even when the host does not conform to Posix. */ #define ISDIGIT(c) ((unsigned) (c) - '0' <= 9) -#if defined (HAVE_UNISTD_H) -#include -#endif - -#if defined (_POSIX_VERSION) -/* POSIX does not require that the d_ino field be present, and some - systems do not provide it. */ -# define REAL_DIR_ENTRY(dp) 1 -#else +#if D_INO_IN_DIRENT # define REAL_DIR_ENTRY(dp) ((dp)->d_ino != 0) +#else +# define REAL_DIR_ENTRY(dp) 1 #endif -/* Which type of backup file names are generated. */ -enum backup_type backup_type = none; - /* The extension added to file names to produce a simple (as opposed to numbered) backup file name. */ -char *simple_backup_suffix = "~"; +const char *simple_backup_suffix = "~"; -char *basename (); -char *dirname (); -static char *concat (); -char *find_backup_file_name (); -static char *make_version_name (); -static int max_backup_version (); -static int version_number (); +static int max_backup_version PARAMS ((const char *, const char *)); +static int version_number PARAMS ((const char *, const char *, size_t)); /* Return the name of the new backup file for file FILE, allocated with malloc. Return 0 if out of memory. @@ -113,41 +116,56 @@ static int version_number (); Do not call this function if backup_type == none. */ char * -find_backup_file_name (file) - const char *file; +find_backup_file_name (const char *file, enum backup_type backup_type) { - char *dir; - char *base_versions; - int highest_backup; - - if (backup_type == simple) - return concat (file, simple_backup_suffix); - base_versions = concat (basename (file), ".~"); - if (base_versions == 0) - return 0; - dir = dirname (file); - if (dir == 0) + size_t backup_suffix_size_max; + size_t file_len = strlen (file); + size_t numbered_suffix_size_max = INT_STRLEN_BOUND (int) + 4; + char *s; + const char *suffix = simple_backup_suffix; + + /* Allow room for simple or `.~N~' backups. */ + backup_suffix_size_max = strlen (simple_backup_suffix) + 1; + if (HAVE_DIR && backup_suffix_size_max < numbered_suffix_size_max) + backup_suffix_size_max = numbered_suffix_size_max; + + s = malloc (file_len + backup_suffix_size_max + numbered_suffix_size_max); + if (s) { - free (base_versions); - return 0; + strcpy (s, file); + +#if HAVE_DIR + if (backup_type != simple) + { + int highest_backup; + size_t dir_len = base_name (s) - s; + + strcpy (s + dir_len, "."); + highest_backup = max_backup_version (file + dir_len, s); + if (! (backup_type == numbered_existing && highest_backup == 0)) + { + char *numbered_suffix = s + (file_len + backup_suffix_size_max); + sprintf (numbered_suffix, ".~%d~", highest_backup + 1); + suffix = numbered_suffix; + } + strcpy (s, file); + } +#endif /* HAVE_DIR */ + + addext (s, suffix, '~'); } - highest_backup = max_backup_version (base_versions, dir); - free (base_versions); - free (dir); - if (backup_type == numbered_existing && highest_backup == 0) - return concat (file, simple_backup_suffix); - return make_version_name (file, highest_backup + 1); + return s; } +#if HAVE_DIR + /* Return the number of the highest-numbered backup file for file FILE in directory DIR. If there are no numbered backups of FILE in DIR, or an error occurs reading DIR, return 0. - FILE should already have ".~" appended to it. */ + */ static int -max_backup_version (file, dir) - const char *file; - const char *dir; +max_backup_version (const char *file, const char *dir) { DIR *dirp; struct dirent *dp; @@ -164,7 +182,7 @@ max_backup_version (file, dir) while ((dp = readdir (dirp)) != 0) { - if (!REAL_DIR_ENTRY (dp) || NLENGTH (dp) <= file_name_length) + if (!REAL_DIR_ENTRY (dp) || NLENGTH (dp) < file_name_length + 4) continue; this_version = version_number (file, dp->d_name, file_name_length); @@ -176,62 +194,75 @@ max_backup_version (file, dir) return highest_version; } -/* Return a string, allocated with malloc, containing - "FILE.~VERSION~". Return 0 if out of memory. */ - -static char * -make_version_name (file, version) - const char *file; - int version; -{ - char *backup_name; - - backup_name = malloc (strlen (file) + 16); - if (backup_name == 0) - return 0; - sprintf (backup_name, "%s.~%d~", file, version); - return backup_name; -} - /* If BACKUP is a numbered backup of BASE, return its version number; otherwise return 0. BASE_LENGTH is the length of BASE. - BASE should already have ".~" appended to it. */ + */ static int -version_number (base, backup, base_length) - const char *base; - const char *backup; - int base_length; +version_number (const char *base, const char *backup, size_t base_length) { int version; const char *p; version = 0; - if (!strncmp (base, backup, base_length) && ISDIGIT (backup[base_length])) + if (strncmp (base, backup, base_length) == 0 + && backup[base_length] == '.' + && backup[base_length + 1] == '~') { - for (p = &backup[base_length]; ISDIGIT (*p); ++p) + for (p = &backup[base_length + 2]; ISDIGIT (*p); ++p) version = version * 10 + *p - '0'; if (p[0] != '~' || p[1]) version = 0; } return version; } +#endif /* HAVE_DIR */ -/* Return the newly-allocated concatenation of STR1 and STR2. - If out of memory, return 0. */ - -static char * -concat (str1, str2) - const char *str1; - const char *str2; +static const char * const backup_args[] = { - char *newstr; - int str1_length = strlen (str1); + /* In a series of synonyms, present the most meaning full first, so + that argmatch_valid be more readable. */ + "none", "off", + "simple", "never", + "existing", "nil", + "numbered", "t", + 0 +}; + +static const enum backup_type backup_types[] = +{ + none, none, + simple, simple, + numbered_existing, numbered_existing, + numbered, numbered +}; + +/* Return the type of backup specified by VERSION. + If VERSION is NULL or the empty string, return numbered_existing. + If VERSION is invalid or ambiguous, fail with a diagnostic appropriate + for the specified CONTEXT. Unambiguous abbreviations are accepted. */ + +enum backup_type +get_version (const char *context, const char *version) +{ + if (version == 0 || *version == 0) + return numbered_existing; + else + return XARGMATCH (context, version, backup_args, backup_types); +} - newstr = malloc (str1_length + strlen (str2) + 1); - if (newstr == 0) - return 0; - strcpy (newstr, str1); - strcpy (newstr + str1_length, str2); - return newstr; + +/* Return the type of backup specified by VERSION. + If VERSION is NULL, use the value of the envvar VERSION_CONTROL. + If the specified string is invalid or ambiguous, fail with a diagnostic + appropriate for the specified CONTEXT. + Unambiguous abbreviations are accepted. */ + +enum backup_type +xget_version (const char *context, const char *version) +{ + if (version && *version) + return get_version (context, version); + else + return get_version ("$VERSION_CONTROL", getenv ("VERSION_CONTROL")); }