Re: file-truename in Windows native build

I'm going to apply this unless anyone has any objections. I don't think it conflicts with Mike's patch and adds functionality for cygwin. andy At 12:23 AM 9/1/00 +0200, Dan Holmsand wrote: > Mike Alexander <mta(a)arbortext.com&gt; writes: > > > It's annoyed me for some time that the native Windows version > > of XEmacs often ends up with two (or more) buffers visiting > > the same file, even if find-file-compare-truenames or > > find-file-use-truenames is set. > > I totally agree. In fact I also started to fix this a while > ago... > > [...] > > > The attached patch changed Ffile_truename to use > > win32_get_long_filename on Windows after changing it to do > > something reasonable when given a path that contains a file or > > directory that doesn't exist. This latter change might cause > > a problem with code that used win32-long-file-name to test for > > the existence of a file, but I can't find any code that uses > > it at all, let alone for that purpose. I also changed > > xemacs.mak to remove realpath.c from the native Windows build > > since it isn't needed anymore. With this patch I haven't had > > any more problems with multiple buffers visiting the same file > > if I set find-file-compare-truenames or > > find-file-use-truenames. > > I chose the other alternative - making xrealpath work on > windows. I obviously think this is a better choice, mainly > because it's mine :-) > > My code have some real advantages, though. Mainly, it also works > with cygwin xemacs, which is broken in basically the same way as > the native built one. Besides that the current code doesn't care > for case or short filenames, it is totally broken when you feed > it UNC paths. > > My code deals with UNC paths by lower-casing the server and share > parts of the filename (i.e. //server/share/...), since case is > not significant here. > > It is perhaps also an advantage that the code is shared between > unix, cygwin and native windows xemacsen. It should, for > example, be quite easy to add support for Win2k's reparse points > (which basically work like symlinks). > > I also definitely think find-file-compare-truenames should be > true by default on windows. > > Anyway, here it is. I've been using it for a while, on both > native xemacs and cygwin. However, I haven't tested the code on > unix (the changes there are mainly trivial, though; mostly *s == > '/' -> IS_DIRECTORY_SEP (*s), etc.). > > /dan > > -- > Dan Ola Holmsand > IB > dan(a)eyebee.com > > > > 2000-08-31 Dan Holmsand <dan(a)eyebee.com&gt; > > * buffer.c: Make find-file-compare-truenames default to > true on windows. > > * realpath.c (win32_abs_start): > (cygwin_readlink): > (win32_readlink): New functions. > (xrealpath): Return really real filenames on windows. > > * fileio.c (Ffile_truename): Make file-truename work on > windows. > > Index: src/buffer.c > ================================================================ > === RCS file: /usr/CVSroot/XEmacs/xemacs/src/buffer.c,v > retrieving revision 1.36.2.38 > diff -u -u -r1.36.2.38 buffer.c > --- buffer.c 2000/08/18 17:16:00 1.36.2.38 > +++ buffer.c 2000/08/31 21:19:18 > ＠＠ -2227,7 +2227,11 ＠＠ > > See also the variable find-file-use-truenames. > */ ); > +#if defined(CYGWIN) || defined(WIN32_NATIVE) > + find_file_compare_truenames = 1; > +#else > find_file_compare_truenames = 0; > +#endif > > DEFVAR_BOOL ("find-file-use-truenames", > &find_file_use_truenames /* If this is true, then a buffer's > visited file-name will always be Index: src/fileio.c > ================================================================ > === RCS file: /usr/CVSroot/XEmacs/xemacs/src/fileio.c,v > retrieving revision 1.51.2.26 > diff -u -u -r1.51.2.26 fileio.c > --- fileio.c 2000/08/06 09:27:12 1.51.2.26 > +++ fileio.c 2000/08/31 21:19:40 > ＠＠ -1316,14 +1316,30 ＠＠ > we just use our own version in realpath.c. */ > for (;;) > { > - p = (Extbyte *) memchr (p + 1, '/', elen - (p + 1 - > path)); - if (p) > - *p = 0; > + Extbyte *pos; > > +#ifdef WIN32_NATIVE > + if (IS_DRIVE (p[0]) && IS_DEVICE_SEP (p[1]) > + && IS_DIRECTORY_SEP (p[2])) > + /* don't test c: on windows */ > + p = p+2; > + else if (IS_DIRECTORY_SEP (p[0]) && IS_DIRECTORY_SEP > (p[1])) + /* start after // */ > + p = p+1; > +#endif > + for (pos = p + 1; pos < path + elen; pos++) > + if (IS_DIRECTORY_SEP (*pos)) > + { > + *(p = pos) = 0; > + break; > + } > + if (p != pos) > + p = 0; > + > if (xrealpath ((char *) path, resolved_path)) > { > if (p) > - *p = '/'; > + *p = DIRECTORY_SEP; > else > break; > > ＠＠ -1342,13 +1358,13 ＠＠ > { > int plen = elen - (p - path); > > - if (rlen > 1 && resolved_path[rlen - 1] == > '/') + if (rlen > 1 && IS_DIRECTORY_SEP > (resolved_path[rlen - 1])) > rlen = rlen - 1; > > if (plen + rlen + 1 > countof > (resolved_path)) goto toolong; > > - resolved_path[rlen] = '/'; > + resolved_path[rlen] = DIRECTORY_SEP; > memcpy (resolved_path + rlen + 1, p + 1, > plen + 1 - 1); } > break; > ＠＠ -1361,12 +1377,12 ＠＠ > { > Lisp_Object resolved_name; > int rlen = strlen (resolved_path); > - if (elen > 0 && XSTRING_BYTE (expanded_name, elen - 1) == > '/' - && !(rlen > 0 && resolved_path[rlen - 1] == '/')) > + if (elen > 0 && IS_DIRECTORY_SEP (XSTRING_BYTE > (expanded_name, elen - 1)) > + && !(rlen > 0 && IS_DIRECTORY_SEP (resolved_path[rlen > - 1]))) { > if (rlen + 1 > countof (resolved_path)) > goto toolong; > - resolved_path[rlen++] = '/'; > + resolved_path[rlen++] = DIRECTORY_SEP; > resolved_path[rlen] = '\0'; > } > TO_INTERNAL_FORMAT (DATA, (resolved_path, rlen), > Index: src/realpath.c > ================================================================ > === RCS file: /usr/CVSroot/XEmacs/xemacs/src/realpath.c,v > retrieving revision 1.6.2.7 > diff -u -u -r1.6.2.7 realpath.c > --- realpath.c 2000/06/12 04:18:21 1.6.2.7 > +++ realpath.c 2000/08/31 21:19:47 > ＠＠ -23,42 +23,145 ＠＠ > /* Synched up with: Not in FSF. */ > > #include <config.h> > +#include "lisp.h" > +#include "sysfile.h" > > -#include <sys/types.h> > #include <stdio.h> > #include <string.h> > -#include <errno.h> > #include <limits.h> > > -#ifdef HAVE_UNISTD_H > -#include <unistd.h> > -#endif > +/* First char after start of absolute filename. */ > +#define ABS_START(name) (name + ABS_LENGTH (name)) > > -#if defined (HAVE_SYS_PARAM_H) > -#include <sys/param.h> > -#endif > +#if defined (WIN32_NATIVE) > +/* Length of start of absolute filename. */ > +# define ABS_LENGTH(name) (win32_abs_start (name)) > +static int win32_abs_start (const char * name); > +/* System dependent version of readlink. */ > +# define sys_readlink(name, buf, size) win32_readlink (name, > buf, size) +#else > +# ifdef CYGWIN > +# define ABS_LENGTH(name) (IS_DIRECTORY_SEP (*name) ? \ > + (IS_DIRECTORY_SEP (name[1]) ? 2 : > 1) : 0) +# define sys_readlink(name, buf, size) cygwin_readlink > (name, buf, size) +# else > +# define ABS_LENGTH(name) (IS_DIRECTORY_SEP (*name) ? 1 : 0) > +# define sys_readlink(name, buf, size) readlink (name, buf, > size) +# endif /* CYGWIN */ > +#endif /* WIN32_NATIVE */ > + > +#if defined (WIN32_NATIVE) || defined (CYGWIN) > +#include "syswindows.h" > +/* Emulate readlink on win32 - finds real name (i.e. correct > case) of + a file. UNC servers and shares are lower-cased. > Directories must be + given without trailing '/'. One day, > this could read Win2K's + reparse points. */ > +static int > +win32_readlink (const char * name, char * buf, int size) > +{ > + WIN32_FIND_DATA find_data; > + HANDLE dir_handle = NULL; > + int len = 0; > + int err = 0; > + const char* lastname; > + int count = 0; > + const char* tmp; > + char* res = NULL; > + > + assert (*name); > + > + /* Sort of check we have a valid filename. */ > + if (strpbrk (name, "*?|<>\"") || strlen (name) >= MAX_PATH) > + { > + errno = EIO; > + return -1; > + } > + > + /* Find start of filename */ > + lastname = name + strlen (name); > + while (lastname > name && !IS_DIRECTORY_SEP (lastname[-1])) > + --lastname; > + > + /* Count slashes in unc path */ > + if (ABS_LENGTH (name) == 2) > + for (tmp = name; *tmp; tmp++) > + if (IS_DIRECTORY_SEP (*tmp)) > + count++; > + > + if (count >= 2 && count < 4) > + { > + /* UNC server or share name: just copy lowercased name. */ > + res = find_data.cFileName; > + for (tmp = lastname; *tmp; tmp++) > + *res++ = tolower (*tmp); > + *res = '\0'; > + } > + else > + dir_handle = FindFirstFile (name, &find_data); > + > + if (res || dir_handle != INVALID_HANDLE_VALUE) > + { > + if ((len = strlen (find_data.cFileName)) < size) > + { > + if (strcmp (lastname, find_data.cFileName) == 0) > + /* Signal that the name is already OK. */ > + err = EINVAL; > + else > + memcpy (buf, find_data.cFileName, len + 1); > + } > + else > + err = ENAMETOOLONG; > + if (!res) FindClose (dir_handle); > + } > + else > + err = ENOENT; > > + errno = err; > + return err ? -1 : len; > +} > +#endif /* WIN32_NATIVE || CYGWIN */ > + > +#ifdef CYGWIN > +/* Call readlink and try to find out the correct case for the > file. */ +static int > +cygwin_readlink (const char * name, char * buf, int size) > +{ > + int n = readlink (name, buf, size); > + if (n < 0) > + { > + /* The file may exist, but isn't a symlink. Try to find > the + right name. */ > + char* tmp = alloca > (cygwin_posix_to_win32_path_list_buf_size (name)); + > cygwin_posix_to_win32_path_list (name, tmp); > + n = win32_readlink (tmp, buf, size); > + } > + return n; > +} > +#endif /* CYGWIN */ > + > #ifdef WIN32_NATIVE > -#include <direct.h> > +#ifndef ELOOP > +#define ELOOP 10062 /* = WSAELOOP in winsock.h */ > #endif > - > -#include <sys/stat.h> /* for S_IFLNK */ > +/* Length of start of absolute filename. */ > +static int > +win32_abs_start (const char * name) > +{ > + if (isalpha (*name) && IS_DEVICE_SEP (name[1]) > + && IS_DIRECTORY_SEP (name[2])) > + return 3; > + else if (IS_DIRECTORY_SEP (*name)) > + return IS_DIRECTORY_SEP (name[1]) ? 2 : 1; > + else > + return 0; > +} > +#endif /* WIN32_NATIVE */ > > #if !defined (HAVE_GETCWD) && defined (HAVE_GETWD) > #undef getcwd > #define getcwd(buffer, len) getwd (buffer) > #endif > > -#ifndef PATH_MAX > -# if defined (_POSIX_PATH_MAX) > -# define PATH_MAX _POSIX_PATH_MAX > -# elif defined (MAXPATHLEN) > -# define PATH_MAX MAXPATHLEN > -# else > -# define PATH_MAX 1024 > -# endif > -#endif > - > #define MAX_READLINKS 32 > > char * xrealpath (const char *path, char resolved_path []); > ＠＠ -68,78 +171,63 ＠＠ > char copy_path[PATH_MAX]; > char *new_path = resolved_path; > char *max_path; > -#ifdef S_IFLNK > +#if defined (S_IFLNK) || defined (WIN32_NATIVE) > int readlinks = 0; > char link_path[PATH_MAX]; > int n; > + int abslen = ABS_LENGTH (path); > #endif > > /* Make a copy of the source path since we may need to modify > it. */ strcpy (copy_path, path); > path = copy_path; > max_path = copy_path + PATH_MAX - 2; > + > #ifdef WIN32_NATIVE > - /* > - ** In NT we have two different cases: (1) the path name > begins - ** with a drive letter, e.g., "C:"; and (2) the path > name begins - ** with just a slash, which roots to the current > drive. In the - ** first case we are going to leave things > alone, in the second - ** case we will prepend the drive letter > to the given path. - ** Note: So far in testing, I'm only > seeing case #1, even though - ** I've tried to get the other > cases to happen. > - ** August Hill, 31 Aug 1997. > - ** > - ** Check for a driver letter...C:/... > - */ > - if (*(path + 1) == ':') > + /* Check for c:/... or //server/... */ > + if (abslen == 2 || abslen == 3) > { > - strncpy(new_path, path, 3); > - new_path += 3; > - path += 3; > + strncpy (new_path, path, abslen); > + new_path += abslen; > + path += abslen; > } > - > - /* > - ** No drive letter, but a beginning slash? Prepend the drive > - ** letter... > - */ > - else if (*path == '/') > + /* No drive letter, but a beginning slash? Prepend drive > letter. */ + else if (abslen == 1) > { > getcwd (new_path, PATH_MAX - 1); > new_path += 3; > path++; > } > - > - /* > - ** Just a path name, prepend the current directory > - */ > + /* Just a path name, prepend the current directory */ > else > { > getcwd (new_path, PATH_MAX - 1); > - new_path += strlen(new_path); > - if (new_path[-1] != '/') > - *new_path++ = '/'; > + new_path += strlen (new_path); > + if (!IS_DIRECTORY_SEP (new_path[-1])) > + *new_path++ = DIRECTORY_SEP; > } > - > #else > /* If it's a relative pathname use getcwd for starters. */ > - if (*path != '/') > + if (abslen == 0) > { > getcwd (new_path, PATH_MAX - 1); > - new_path += strlen(new_path); > - if (new_path[-1] != '/') > - *new_path++ = '/'; > + new_path += strlen (new_path); > + if (!IS_DIRECTORY_SEP (new_path[-1])) > + *new_path++ = DIRECTORY_SEP; > } > else > { > - *new_path++ = '/'; > - path++; > + /* Copy first directory sep. May have two on cygwin. */ > + strncpy (new_path, path, abslen); > + new_path += abslen; > + path += abslen; > } > #endif > /* Expand each slash-separated pathname component. */ > while (*path != '\0') > { > /* Ignore stray "/". */ > - if (*path == '/') > + if (IS_DIRECTORY_SEP (*path)) > { > path++; > continue; > ＠＠ -148,7 +236,7 ＠＠ > if (*path == '.') > { > /* Ignore ".". */ > - if (path[1] == '\0' || path[1] == '/') > + if (path[1] == '\0' || IS_DIRECTORY_SEP (path[1])) > { > path++; > continue; > ＠＠ -156,23 +244,24 ＠＠ > > /* Handle ".." */ > if (path[1] == '.' && > - (path[2] == '\0' || path[2] == '/')) > + (path[2] == '\0' || IS_DIRECTORY_SEP (path[2]))) > { > path += 2; > > /* Ignore ".." at root. */ > - if (new_path == resolved_path + 1) > + if (new_path == ABS_START (resolved_path)) > continue; > > /* Handle ".." by backing up. */ > - while ((--new_path)[-1] != '/') > - ; > + --new_path; > + while (!IS_DIRECTORY_SEP (new_path[-1])) > + --new_path; > continue; > } > } > > /* Safely copy the next pathname component. */ > - while (*path != '\0' && *path != '/') > + while (*path != '\0' && !IS_DIRECTORY_SEP (*path)) > { > if (path > max_path) > { > ＠＠ -182,10 +271,10 ＠＠ > *new_path++ = *path++; > } > > -#ifdef S_IFLNK > +#if defined (S_IFLNK) || defined (WIN32_NATIVE) > /* See if latest pathname component is a symlink. */ > *new_path = '\0'; > - n = readlink (resolved_path, link_path, PATH_MAX - 1); > + n = sys_readlink (resolved_path, link_path, PATH_MAX - 1); > > if (n < 0) > { > ＠＠ -204,14 +293,14 ＠＠ > > /* Note: readlink doesn't add the null byte. */ > link_path[n] = '\0'; > - > - if (*link_path == '/') > + > + if (ABS_LENGTH (link_path) > 0) > /* Start over for an absolute symlink. */ > - new_path = resolved_path; > + new_path = resolved_path + ABS_LENGTH (link_path) - > 1; else > /* Otherwise back up over this component. */ > - while (*(--new_path) != '/') > - ; > + for (--new_path; !IS_DIRECTORY_SEP (*new_path); > --new_path) + assert (new_path > resolved_path); > > /* Safe sex check. */ > if (strlen(path) + n >= PATH_MAX) > ＠＠ -225,15 +314,21 ＠＠ > strcpy(copy_path, link_path); > path = copy_path; > } > -#endif /* S_IFLNK */ > - *new_path++ = '/'; > +#endif /* S_IFLNK || WIN32_NATIVE */ > + *new_path++ = DIRECTORY_SEP; > } > > /* Delete trailing slash but don't whomp a lone slash. */ > - if (new_path != resolved_path + 1 && new_path[-1] == '/') > + if (new_path != ABS_START (resolved_path) && IS_DIRECTORY_SEP > (new_path[-1])) > new_path--; > > /* Make sure it's null terminated. */ > *new_path = '\0'; > + > +#ifdef WIN32_NATIVE > + if (ABS_LENGTH (resolved_path) == 3) > + /* Lowercase drive letter. */ > + *resolved_path = tolower (*resolved_path); > +#endif > return resolved_path; > } -------------------------------------------------------------- Dr Andy Piper Principal Consultant, BEA Systems Ltd