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Diffstat (limited to 'contrib/cvs/src/hardlink.c')
| -rw-r--r-- | contrib/cvs/src/hardlink.c | 307 |
1 files changed, 0 insertions, 307 deletions
diff --git a/contrib/cvs/src/hardlink.c b/contrib/cvs/src/hardlink.c deleted file mode 100644 index ed05033..0000000 --- a/contrib/cvs/src/hardlink.c +++ /dev/null @@ -1,307 +0,0 @@ -/* 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 - the Free Software Foundation; either version 2, or (at your option) - any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. */ - -/* Collect and manage hardlink info associated with a particular file. */ - -#include "cvs.h" - -#ifdef PRESERVE_PERMISSIONS_SUPPORT -# include "hardlink.h" - -/* The structure currently used to manage hardlink info is a list. - Therefore, most of the functions which manipulate hardlink data - are walklist procedures. This is not a very efficient implementation; - if someone decides to use a real hash table (for instance), then - much of this code can be rewritten to be a little less arcane. - - Each element of `hardlist' represents an inode. It is keyed on the - inode number, and points to a list of files. This is to make it - easy to find out what files are linked to a given file FOO: find - FOO's inode, look it up in hardlist, and retrieve the list of files - associated with that inode. - - Each file node, in turn, is represented by a `hardlink_info' struct, - which includes `status' and `links' fields. The `status' field should - be used by a procedure like commit_fileproc or update_fileproc to - record each file's status; that way, after all file links have been - recorded, CVS can check the linkage of files which are in doubt - (i.e. T_NEEDS_MERGE files). - - TODO: a diagram of an example hardlist would help here. */ - -/* TODO: change this to something with a marginal degree of - efficiency, like maybe a hash table. Yeah. */ - -List *hardlist; /* Record hardlink information for working files */ -char *working_dir; /* The top-level working directory, used for - constructing full pathnames. */ - -/* Return a pointer to FILEPATH's node in the hardlist. This means - looking up its inode, retrieving the list of files linked to that - inode, and then looking up FILE in that list. If the file doesn't - seem to exist, return NULL. */ -Node * -lookup_file_by_inode (filepath) - const char *filepath; -{ - char *inodestr, *file; - struct stat sb; - Node *hp, *p; - - /* Get file's basename, so that we can stat it. */ - file = strrchr (filepath, '/'); - if (file) - ++file; - else - file = (char *) filepath; - - /* inodestr contains the hexadecimal representation of an - inode, so it requires two bytes of text to represent - each byte of the inode number. */ - inodestr = (char *) xmalloc (2*sizeof(ino_t) + 1); - if (stat (file, &sb) < 0) - { - if (existence_error (errno)) - { - /* The file doesn't exist; we may be doing an update on a - file that's been removed. A nonexistent file has no - link information, so return without changing hardlist. */ - free (inodestr); - return NULL; - } - error (1, errno, "cannot stat %s", file); - } - - sprintf (inodestr, "%lx", (unsigned long) sb.st_ino); - - /* Find out if this inode is already in the hardlist, adding - a new entry to the list if not. */ - hp = findnode (hardlist, inodestr); - if (hp == NULL) - { - hp = getnode (); - hp->type = NT_UNKNOWN; - hp->key = inodestr; - hp->data = getlist(); - hp->delproc = dellist; - (void) addnode (hardlist, hp); - } - else - { - free (inodestr); - } - - p = findnode (hp->data, filepath); - if (p == NULL) - { - p = getnode(); - p->type = NT_UNKNOWN; - p->key = xstrdup (filepath); - p->data = NULL; - (void) addnode (hp->data, p); - } - - return p; -} - -/* After a file has been checked out, add a node for it to the hardlist - (if necessary) and mark it as checked out. */ -void -update_hardlink_info (file) - const char *file; -{ - char *path; - Node *n; - struct hardlink_info *hlinfo; - - if (file[0] == '/') - { - path = xstrdup (file); - } - else - { - /* file is a relative pathname; assume it's from the current - working directory. */ - char *dir = xgetwd(); - path = xmalloc (strlen(dir) + strlen(file) + 2); - sprintf (path, "%s/%s", dir, file); - free (dir); - } - - n = lookup_file_by_inode (path); - if (n == NULL) - { - /* Something is *really* wrong if the file doesn't exist here; - update_hardlink_info should be called only when a file has - just been checked out to a working directory. */ - error (1, 0, "lost hardlink info for %s", file); - } - - if (n->data == NULL) - n->data = xmalloc (sizeof (struct hardlink_info)); - hlinfo = n->data; - hlinfo->status = T_UPTODATE; - hlinfo->checked_out = 1; -} - -/* Return a List with all the files known to be linked to FILE in - the working directory. Used by special_file_mismatch, to determine - whether it is safe to merge two files. - - FIXME: What is the memory allocation for the return value? We seem - to sometimes allocate a new list (getlist() call below) and sometimes - return an existing list (where we return n->data). */ -List * -list_linked_files_on_disk (file) - char *file; -{ - char *inodestr, *path; - struct stat sb; - Node *n; - - /* If hardlist is NULL, we have not been doing an operation that - would permit us to know anything about the file's hardlinks - (cvs update, cvs commit, etc). Return an empty list. */ - if (hardlist == NULL) - return getlist(); - - /* Get the full pathname of file (assuming the working directory) */ - if (file[0] == '/') - path = xstrdup (file); - else - { - char *dir = xgetwd(); - path = (char *) xmalloc (strlen(dir) + strlen(file) + 2); - sprintf (path, "%s/%s", dir, file); - free (dir); - } - - /* We do an extra lookup_file here just to make sure that there - is a node for `path' in the hardlist. If that were not so, - comparing the working directory linkage against the repository - linkage for a file would always fail. */ - (void) lookup_file_by_inode (path); - - if (stat (path, &sb) < 0) - error (1, errno, "cannot stat %s", file); - /* inodestr contains the hexadecimal representation of an - inode, so it requires two bytes of text to represent - each byte of the inode number. */ - inodestr = (char *) xmalloc (2*sizeof(ino_t) + 1); - sprintf (inodestr, "%lx", (unsigned long) sb.st_ino); - - /* Make sure the files linked to this inode are sorted. */ - n = findnode (hardlist, inodestr); - sortlist (n->data, fsortcmp); - - free (inodestr); - return n->data; -} - -/* Compare the files in the `key' fields of two lists, returning 1 if - the lists are equivalent and 0 otherwise. - - Only the basenames of each file are compared. This is an awful hack - that exists because list_linked_files_on_disk returns full paths - and the `hardlinks' structure of a RCSVers node contains only - basenames. That in turn is a result of the awful hack that only - basenames are stored in the RCS file. If anyone ever solves the - problem of correctly managing cross-directory hardlinks, this - function (along with most functions in this file) must be fixed. */ - -int -compare_linkage_lists (links1, links2) - List *links1; - List *links2; -{ - Node *n1, *n2; - char *p1, *p2; - - sortlist (links1, fsortcmp); - sortlist (links2, fsortcmp); - - n1 = links1->list->next; - n2 = links2->list->next; - - while (n1 != links1->list && n2 != links2->list) - { - /* Get the basenames of both files. */ - p1 = strrchr (n1->key, '/'); - if (p1 == NULL) - p1 = n1->key; - else - ++p1; - - p2 = strrchr (n2->key, '/'); - if (p2 == NULL) - p2 = n2->key; - else - ++p2; - - /* Compare the files' basenames. */ - if (strcmp (p1, p2) != 0) - return 0; - - n1 = n1->next; - n2 = n2->next; - } - - /* At this point we should be at the end of both lists; if not, - one file has more links than the other, and return 1. */ - return (n1 == links1->list && n2 == links2->list); -} - -/* Find a checked-out file in a list of filenames. Used by RCS_checkout - when checking out a new hardlinked file, to decide whether this file - can be linked to any others that already exist. The return value - is not currently used. */ - -int -find_checkedout_proc (node, data) - Node *node; - void *data; -{ - Node **uptodate = (Node **) data; - Node *link; - char *dir = xgetwd(); - char *path; - struct hardlink_info *hlinfo; - - /* If we have already found a file, don't do anything. */ - if (*uptodate != NULL) - return 0; - - /* Look at this file in the hardlist and see whether the checked_out - field is 1, meaning that it has been checked out during this CVS run. */ - path = (char *) - xmalloc (strlen (dir) + strlen (node->key) + 2); - sprintf (path, "%s/%s", dir, node->key); - link = lookup_file_by_inode (path); - free (path); - free (dir); - - if (link == NULL) - { - /* We haven't seen this file -- maybe it hasn't been checked - out yet at all. */ - return 0; - } - - hlinfo = link->data; - if (hlinfo->checked_out) - { - /* This file has been checked out recently, so it's safe to - link to it. */ - *uptodate = link; - } - - return 0; -} -#endif /* PRESERVE_PERMISSIONS_SUPPORT */ |
