added blocking-io docs

[rsync/rsync.git] / flist.c

/* 
   Copyright (C) Andrew Tridgell 1996
   Copyright (C) Paul Mackerras 1996
   
   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 of the License, 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.
   
   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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

/* generate and receive file lists */

#include "rsync.h"

extern struct stats stats;

extern int verbose;
extern int am_server;
extern int always_checksum;

extern int cvs_exclude;

extern int recurse;

extern int one_file_system;
extern int make_backups;
extern int preserve_links;
extern int preserve_hard_links;
extern int preserve_perms;
extern int preserve_devices;
extern int preserve_uid;
extern int preserve_gid;
extern int preserve_times;
extern int relative_paths;
extern int copy_links;
extern int copy_unsafe_links;
extern int remote_version;
extern int io_error;
extern int sanitize_paths;

static char topsrcname[MAXPATHLEN];

static struct exclude_struct **local_exclude_list;

static void clean_flist(struct file_list *flist, int strip_root);


static void list_file_entry(struct file_struct *f)
{
	char perms[11] = "----------";
	char *perm_map = "rwxrwxrwx";
	int i;

	if (!f->basename)
		/* this can happen if duplicate names were removed */
		return;

	for (i=0;i<9;i++) {
		if (f->mode & (1<<i)) perms[9-i] = perm_map[8-i];
	}
	if (S_ISLNK(f->mode)) perms[0] = 'l';
	if (S_ISDIR(f->mode)) perms[0] = 'd';
	if (S_ISBLK(f->mode)) perms[0] = 'b';
	if (S_ISCHR(f->mode)) perms[0] = 'c';
	if (S_ISSOCK(f->mode)) perms[0] = 's';
	if (S_ISFIFO(f->mode)) perms[0] = 'p';
	
	if (preserve_links && S_ISLNK(f->mode)) {
		rprintf(FINFO,"%s %11.0f %s %s -> %s\n", 
			perms, 
			(double)f->length, timestring(f->modtime), 
			f_name(f), f->link);
	} else {
		rprintf(FINFO,"%s %11.0f %s %s\n", 
			perms, 
			(double)f->length, timestring(f->modtime), f_name(f));
	}
}


int readlink_stat(const char *Path, STRUCT_STAT *Buffer, char *Linkbuf) 
{
#if SUPPORT_LINKS
	if (copy_links) {
		return do_stat(Path, Buffer);
	}
	if (do_lstat(Path, Buffer) == -1) {
		return -1;
	}
	if (S_ISLNK(Buffer->st_mode)) {
		int l;
		if ((l = readlink(Path,Linkbuf,MAXPATHLEN-1)) == -1) {
			return -1;
		}
		Linkbuf[l] = 0;
		if (copy_unsafe_links && (topsrcname[0] != '\0') &&
				    unsafe_symlink(Linkbuf, topsrcname)) {
			return do_stat(Path, Buffer);
		}
	}
	return 0;
#else
	return do_stat(Path, Buffer);
#endif
}

int link_stat(const char *Path, STRUCT_STAT *Buffer) 
{
#if SUPPORT_LINKS
    if (copy_links) {
	return do_stat(Path, Buffer);
    } else {
	return do_lstat(Path, Buffer);
    }
#else
    return do_stat(Path, Buffer);
#endif
}

/*
  This function is used to check if a file should be included/excluded
  from the list of files based on its name and type etc
 */
static int match_file_name(char *fname,STRUCT_STAT *st)
{
  if (check_exclude(fname,local_exclude_list,st)) {
    if (verbose > 2)
      rprintf(FINFO,"excluding file %s\n",fname);
    return 0;
  }
  return 1;
}

/* used by the one_file_system code */
static dev_t filesystem_dev;

static void set_filesystem(char *fname)
{
  STRUCT_STAT st;
  if (link_stat(fname,&st) != 0) return;
  filesystem_dev = st.st_dev;
}


static int to_wire_mode(mode_t mode)
{
	if (S_ISLNK(mode) && (S_IFLNK != 0120000)) {
		return (mode & ~(_S_IFMT)) | 0120000;
	}
	return (int)mode;
}

static mode_t from_wire_mode(int mode)
{
	if ((mode & (_S_IFMT)) == 0120000 && (S_IFLNK != 0120000)) {
		return (mode & ~(_S_IFMT)) | S_IFLNK;
	}
	return (mode_t)mode;
}


static void send_directory(int f,struct file_list *flist,char *dir);

static char *flist_dir;


static void send_file_entry(struct file_struct *file,int f,unsigned base_flags)
{
	unsigned char flags;
	static time_t last_time;
	static mode_t last_mode;
	static dev_t last_rdev;
	static uid_t last_uid;
	static gid_t last_gid;
	static char lastname[MAXPATHLEN];
	char *fname;
	int l1,l2;

	if (f == -1) return;

	if (!file) {
		write_byte(f,0);
		return;
	}

	fname = f_name(file);

	flags = base_flags;

	if (file->mode == last_mode) flags |= SAME_MODE;
	if (file->rdev == last_rdev) flags |= SAME_RDEV;
	if (file->uid == last_uid) flags |= SAME_UID;
	if (file->gid == last_gid) flags |= SAME_GID;
	if (file->modtime == last_time) flags |= SAME_TIME;

	for (l1=0;lastname[l1] && (fname[l1] == lastname[l1]) && (l1 < 255);l1++) ;  
	l2 = strlen(fname) - l1;

	if (l1 > 0) flags |= SAME_NAME;
	if (l2 > 255) flags |= LONG_NAME;

	/* we must make sure we don't send a zero flags byte or the other
	   end will terminate the flist transfer */
	if (flags == 0 && !S_ISDIR(file->mode)) flags |= FLAG_DELETE;
	if (flags == 0) flags |= LONG_NAME;

	write_byte(f,flags);  
	if (flags & SAME_NAME)
		write_byte(f,l1);
	if (flags & LONG_NAME)
		write_int(f,l2);
	else
		write_byte(f,l2);
	write_buf(f,fname+l1,l2);

	write_longint(f,file->length);
	if (!(flags & SAME_TIME))
		write_int(f,(int)file->modtime);
	if (!(flags & SAME_MODE))
		write_int(f,to_wire_mode(file->mode));
	if (preserve_uid && !(flags & SAME_UID)) {
		add_uid(file->uid);
		write_int(f,(int)file->uid);
	}
	if (preserve_gid && !(flags & SAME_GID)) {
		add_gid(file->gid);
		write_int(f,(int)file->gid);
	}
	if (preserve_devices && IS_DEVICE(file->mode) && !(flags & SAME_RDEV))
		write_int(f,(int)file->rdev);

#if SUPPORT_LINKS
	if (preserve_links && S_ISLNK(file->mode)) {
		write_int(f,strlen(file->link));
		write_buf(f,file->link,strlen(file->link));
	}
#endif

#if SUPPORT_HARD_LINKS
	if (preserve_hard_links && S_ISREG(file->mode)) {
		write_int(f,(int)file->dev);
		write_int(f,(int)file->inode);
	}
#endif

	if (always_checksum) {
		if (remote_version < 21) {
			write_buf(f,file->sum,2);
		} else {
			write_buf(f,file->sum,MD4_SUM_LENGTH);
		}
	}       

	last_mode = file->mode;
	last_rdev = file->rdev;
	last_uid = file->uid;
	last_gid = file->gid;
	last_time = file->modtime;

	strlcpy(lastname,fname,MAXPATHLEN);
	lastname[MAXPATHLEN-1] = 0;
}



static void receive_file_entry(struct file_struct **fptr,
			       unsigned flags,int f)
{
	static time_t last_time;
	static mode_t last_mode;
	static dev_t last_rdev;
	static uid_t last_uid;
	static gid_t last_gid;
	static char lastname[MAXPATHLEN];
	char thisname[MAXPATHLEN];
	int l1=0,l2=0;
	char *p;
	struct file_struct *file;

	if (flags & SAME_NAME)
		l1 = read_byte(f);
  
	if (flags & LONG_NAME)
		l2 = read_int(f);
	else
		l2 = read_byte(f);

	file = (struct file_struct *)malloc(sizeof(*file));
	if (!file) out_of_memory("receive_file_entry");
	memset((char *)file, 0, sizeof(*file));
	(*fptr) = file;

	if (l2 >= MAXPATHLEN-l1) {
		rprintf(FERROR,"overflow: flags=0x%x l1=%d l2=%d lastname=%s\n",
			flags, l1, l2, lastname);
		overflow("receive_file_entry");
	}

	strlcpy(thisname,lastname,l1+1);
	read_sbuf(f,&thisname[l1],l2);
	thisname[l1+l2] = 0;

	strlcpy(lastname,thisname,MAXPATHLEN);
	lastname[MAXPATHLEN-1] = 0;

	clean_fname(thisname);

	if (sanitize_paths) {
		sanitize_path(thisname, NULL);
	}

	if ((p = strrchr(thisname,'/'))) {
		static char *lastdir;
		*p = 0;
		if (lastdir && strcmp(thisname, lastdir)==0) {
			file->dirname = lastdir;
		} else {
			file->dirname = strdup(thisname);
			lastdir = file->dirname;
		}
		file->basename = strdup(p+1);
	} else {
		file->dirname = NULL;
		file->basename = strdup(thisname);
	}

	if (!file->basename) out_of_memory("receive_file_entry 1");


	file->flags = flags;
	file->length = read_longint(f);
	file->modtime = (flags & SAME_TIME) ? last_time : (time_t)read_int(f);
	file->mode = (flags & SAME_MODE) ? last_mode : from_wire_mode(read_int(f));
	if (preserve_uid)
		file->uid = (flags & SAME_UID) ? last_uid : (uid_t)read_int(f);
	if (preserve_gid)
		file->gid = (flags & SAME_GID) ? last_gid : (gid_t)read_int(f);
	if (preserve_devices && IS_DEVICE(file->mode))
		file->rdev = (flags & SAME_RDEV) ? last_rdev : (dev_t)read_int(f);

	if (preserve_links && S_ISLNK(file->mode)) {
		int l = read_int(f);
		file->link = (char *)malloc(l+1);
		if (!file->link) out_of_memory("receive_file_entry 2");
		read_sbuf(f,file->link,l);
		if (sanitize_paths) {
			sanitize_path(file->link, file->dirname);
		}
	}

#if SUPPORT_HARD_LINKS
	if (preserve_hard_links && S_ISREG(file->mode)) {
		file->dev = read_int(f);
		file->inode = read_int(f);
	}
#endif
  
	if (always_checksum) {
		file->sum = (char *)malloc(MD4_SUM_LENGTH);
		if (!file->sum) out_of_memory("md4 sum");
		if (remote_version < 21) {
			read_buf(f,file->sum,2);
		} else {
			read_buf(f,file->sum,MD4_SUM_LENGTH);
		}
	}
  
	last_mode = file->mode;
	last_rdev = file->rdev;
	last_uid = file->uid;
	last_gid = file->gid;
	last_time = file->modtime;

	if (!preserve_perms) {
		extern int orig_umask;
		/* set an appropriate set of permissions based on original
		   permissions and umask. This emulates what GNU cp does */
		file->mode &= ~orig_umask;
	}
}


/* determine if a file in a different filesstem should be skipped
   when one_file_system is set. We bascally only want to include
   the mount points - but they can be hard to find! */
static int skip_filesystem(char *fname, STRUCT_STAT *st)
{
	STRUCT_STAT st2;
	char *p = strrchr(fname, '/');

	/* skip all but directories */
	if (!S_ISDIR(st->st_mode)) return 1;

	/* if its not a subdirectory then allow */
	if (!p) return 0;

	*p = 0;
	if (link_stat(fname, &st2)) {
		*p = '/';
		return 0;
	}
	*p = '/';
	
	return (st2.st_dev != filesystem_dev);
}

/* create a file_struct for a named file */
struct file_struct *make_file(int f, char *fname)
{
	struct file_struct *file;
	STRUCT_STAT st;
	char sum[SUM_LENGTH];
	char *p;
	char cleaned_name[MAXPATHLEN];
	char linkbuf[MAXPATHLEN];
	extern int delete_excluded;

	strlcpy(cleaned_name, fname, MAXPATHLEN);
	cleaned_name[MAXPATHLEN-1] = 0;
	clean_fname(cleaned_name);
	if (sanitize_paths) {
		sanitize_path(cleaned_name, NULL);
	}
	fname = cleaned_name;

	memset(sum,0,SUM_LENGTH);

	if (readlink_stat(fname,&st,linkbuf) != 0) {
		io_error = 1;
		rprintf(FERROR,"readlink %s: %s\n",
			fname,strerror(errno));
		return NULL;
	}

	if (S_ISDIR(st.st_mode) && !recurse) {
		rprintf(FINFO,"skipping directory %s\n",fname);
		return NULL;
	}
	
	if (one_file_system && st.st_dev != filesystem_dev) {
		if (skip_filesystem(fname, &st))
			return NULL;
	}
	
	/* f is set to -1 when calculating deletion file list */
	if (((f != -1) || !delete_excluded) && !match_file_name(fname,&st))
		return NULL;
	
	if (verbose > 2)
		rprintf(FINFO,"make_file(%d,%s)\n",f,fname);
	
	file = (struct file_struct *)malloc(sizeof(*file));
	if (!file) out_of_memory("make_file");
	memset((char *)file,0,sizeof(*file));

	if ((p = strrchr(fname,'/'))) {
		static char *lastdir;
		*p = 0;
		if (lastdir && strcmp(fname, lastdir)==0) {
			file->dirname = lastdir;
		} else {
			file->dirname = strdup(fname);
			lastdir = file->dirname;
		}
		file->basename = strdup(p+1);
		*p = '/';
	} else {
		file->dirname = NULL;
		file->basename = strdup(fname);
	}

	file->modtime = st.st_mtime;
	file->length = st.st_size;
	file->mode = st.st_mode;
	file->uid = st.st_uid;
	file->gid = st.st_gid;
	file->dev = st.st_dev;
	file->inode = st.st_ino;
#ifdef HAVE_ST_RDEV
	file->rdev = st.st_rdev;
#endif

#if SUPPORT_LINKS
	if (S_ISLNK(st.st_mode)) {
		file->link = strdup(linkbuf);
	}
#endif

	if (always_checksum) {
		file->sum = (char *)malloc(MD4_SUM_LENGTH);
		if (!file->sum) out_of_memory("md4 sum");
		/* drat. we have to provide a null checksum for non-regular
		   files in order to be compatible with earlier versions
		   of rsync */
		if (S_ISREG(st.st_mode)) {
			file_checksum(fname,file->sum,st.st_size);
		} else {
			memset(file->sum, 0, MD4_SUM_LENGTH);
		}
	}       

	if (flist_dir) {
		static char *lastdir;
		if (lastdir && strcmp(lastdir, flist_dir)==0) {
			file->basedir = lastdir;
		} else {
			file->basedir = strdup(flist_dir);
			lastdir = file->basedir;
		}
	} else {
		file->basedir = NULL;
	}

	if (!S_ISDIR(st.st_mode))
		stats.total_size += st.st_size;

	return file;
}



void send_file_name(int f,struct file_list *flist,char *fname,
			   int recursive, unsigned base_flags)
{
  struct file_struct *file;

  file = make_file(f,fname);

  if (!file) return;  
  
  if (flist->count >= flist->malloced) {
	  if (flist->malloced < 1000)
		  flist->malloced += 1000;
	  else
		  flist->malloced *= 2;
	  flist->files = (struct file_struct **)realloc(flist->files,
							sizeof(flist->files[0])*
							flist->malloced);
	  if (!flist->files)
		  out_of_memory("send_file_name");
  }

  if (strcmp(file->basename,"")) {
    flist->files[flist->count++] = file;
    send_file_entry(file,f,base_flags);
  }

  if (S_ISDIR(file->mode) && recursive) {
	  struct exclude_struct **last_exclude_list = local_exclude_list;
	  send_directory(f,flist,f_name(file));
	  local_exclude_list = last_exclude_list;
	  return;
  }
}



static void send_directory(int f,struct file_list *flist,char *dir)
{
	DIR *d;
	struct dirent *di;
	char fname[MAXPATHLEN];
	int l;
	char *p;

	d = opendir(dir);
	if (!d) {
		io_error = 1;
		rprintf(FERROR,"opendir(%s): %s\n",
			dir,strerror(errno));
		return;
	}

	strlcpy(fname,dir,MAXPATHLEN);
	l = strlen(fname);
	if (fname[l-1] != '/') {
		if (l == MAXPATHLEN-1) {
			io_error = 1;
			rprintf(FERROR,"skipping long-named directory %s\n",fname);
			closedir(d);
			return;
		}
		strlcat(fname,"/", MAXPATHLEN);
		l++;
	}
	p = fname + strlen(fname);

	local_exclude_list = NULL;

	if (cvs_exclude) {
		if (strlen(fname) + strlen(".cvsignore") <= MAXPATHLEN-1) {
			strcpy(p,".cvsignore");
			local_exclude_list = make_exclude_list(fname,NULL,0,0);
		} else {
			io_error = 1;
			rprintf(FINFO,"cannot cvs-exclude in long-named directory %s\n",fname);
		}
	}  
	
	for (di=readdir(d); di; di=readdir(d)) {
		char *dname = d_name(di);
		if (strcmp(dname,".")==0 ||
		    strcmp(dname,"..")==0)
			continue;
		strlcpy(p,dname,MAXPATHLEN-l);
		send_file_name(f,flist,fname,recurse,0);
	}

	if (local_exclude_list) {
		add_exclude_list("!", &local_exclude_list, 0);
	}

	closedir(d);
}



struct file_list *send_file_list(int f,int argc,char *argv[])
{
	int i,l;
	STRUCT_STAT st;
	char *p,*dir,*olddir;
	char lastpath[MAXPATHLEN]="";
	struct file_list *flist;
	int64 start_write;

	if (verbose && recurse && !am_server && f != -1) {
		rprintf(FINFO,"building file list ... ");
		rflush(FINFO);
	}

	start_write = stats.total_written;

	flist = (struct file_list *)malloc(sizeof(flist[0]));
	if (!flist) out_of_memory("send_file_list");

	flist->count=0;
	flist->malloced = 1000;
	flist->files = (struct file_struct **)malloc(sizeof(flist->files[0])*
						     flist->malloced);
	if (!flist->files) out_of_memory("send_file_list");

	if (f != -1) {
		io_start_buffering(f);
	}

	for (i=0;i<argc;i++) {
		char *fname = topsrcname;

		strlcpy(fname,argv[i],MAXPATHLEN);

		l = strlen(fname);
		if (l != 1 && fname[l-1] == '/') {
			if ((l == 2) && (fname[0] == '.')) {
				/*  Turn ./ into just . rather than ./.
				    This was put in to avoid a problem with
				      rsync -aR --delete from ./
				    The send_file_name() below of ./ was
				    mysteriously preventing deletes */
				fname[1] = 0;
			} else {
				strlcat(fname,".",MAXPATHLEN);
			}
		}

		if (link_stat(fname,&st) != 0) {
			if (f != -1) {
				io_error=1;
				rprintf(FERROR,"link_stat %s : %s\n",fname,strerror(errno));
			}
			continue;
		}

		if (S_ISDIR(st.st_mode) && !recurse) {
			rprintf(FINFO,"skipping directory %s\n",fname);
			continue;
		}

		dir = NULL;
		olddir = NULL;

		if (!relative_paths) {
			p = strrchr(fname,'/');
			if (p) {
				*p = 0;
				if (p == fname) 
					dir = "/";
				else
					dir = fname;      
				fname = p+1;      
			}
		} else if (f != -1 && (p=strrchr(fname,'/'))) {
			/* this ensures we send the intermediate directories,
			   thus getting their permissions right */
			*p = 0;
			if (strcmp(lastpath,fname)) {
				strlcpy(lastpath, fname, sizeof(lastpath));
				*p = '/';
				for (p=fname+1; (p=strchr(p,'/')); p++) {
					int copy_links_saved = copy_links;
					int recurse_saved = recurse;
					*p = 0;
					copy_links = copy_unsafe_links;
					/* set recurse to 1 to prevent make_file
					   from ignoring directory, but still
					   turn off the recursive parameter to
					   send_file_name */
					recurse = 1;
					send_file_name(f, flist, fname, 0, 0);
					copy_links = copy_links_saved;
					recurse = recurse_saved;
					*p = '/';
				}
			} else {
				*p = '/';
			}
		}
		
		if (!*fname)
			fname = ".";
		
		if (dir && *dir) {
			olddir = push_dir(dir, 1);

			if (!olddir) {
				io_error=1;
				rprintf(FERROR,"push_dir %s : %s\n",
					dir,strerror(errno));
				continue;
			}

			flist_dir = dir;
		}
		
		if (one_file_system)
			set_filesystem(fname);

		send_file_name(f,flist,fname,recurse,FLAG_DELETE);

		if (olddir != NULL) {
			flist_dir = NULL;
			if (pop_dir(olddir) != 0) {
				rprintf(FERROR,"pop_dir %s : %s\n",
					dir,strerror(errno));
				exit_cleanup(RERR_FILESELECT);
			}
		}
	}

	topsrcname[0] = '\0';

	if (f != -1) {
		send_file_entry(NULL,f,0);
	}

	if (verbose && recurse && !am_server && f != -1)
		rprintf(FINFO,"done\n");
	
	clean_flist(flist, 0);
	
	/* now send the uid/gid list. This was introduced in protocol
           version 15 */
	if (f != -1 && remote_version >= 15) {
		send_uid_list(f);
	}

	/* if protocol version is >= 17 then send the io_error flag */
	if (f != -1 && remote_version >= 17) {
		extern int module_id;
		write_int(f, lp_ignore_errors(module_id)? 0 : io_error);
	}

	if (f != -1) {
		io_end_buffering(f);
		stats.flist_size = stats.total_written - start_write;
		stats.num_files = flist->count;
	}

	if (verbose > 2)
		rprintf(FINFO,"send_file_list done\n");

	return flist;
}


struct file_list *recv_file_list(int f)
{
  struct file_list *flist;
  unsigned char flags;
  int64 start_read;
  extern int list_only;

  if (verbose && recurse && !am_server) {
    rprintf(FINFO,"receiving file list ... ");
    rflush(FINFO);
  }

  start_read = stats.total_read;

  flist = (struct file_list *)malloc(sizeof(flist[0]));
  if (!flist)
    goto oom;

  flist->count=0;
  flist->malloced=1000;
  flist->files = (struct file_struct **)malloc(sizeof(flist->files[0])*
					       flist->malloced);
  if (!flist->files)
    goto oom;


  for (flags=read_byte(f); flags; flags=read_byte(f)) {
    int i = flist->count;

    if (i >= flist->malloced) {
	  if (flist->malloced < 1000)
		  flist->malloced += 1000;
	  else
		  flist->malloced *= 2;
	  flist->files =(struct file_struct **)realloc(flist->files,
						       sizeof(flist->files[0])*
						       flist->malloced);
	  if (!flist->files)
		  goto oom;
    }

    receive_file_entry(&flist->files[i],flags,f);

    if (S_ISREG(flist->files[i]->mode))
	    stats.total_size += flist->files[i]->length;

    flist->count++;

    if (verbose > 2)
      rprintf(FINFO,"recv_file_name(%s)\n",f_name(flist->files[i]));
  }


  if (verbose > 2)
    rprintf(FINFO,"received %d names\n",flist->count);

  clean_flist(flist, relative_paths);

  if (verbose && recurse && !am_server) {
    rprintf(FINFO,"done\n");
  }

  /* now recv the uid/gid list. This was introduced in protocol version 15 */
  if (f != -1 && remote_version >= 15) {
	  recv_uid_list(f, flist);
  }

  /* if protocol version is >= 17 then recv the io_error flag */
  if (f != -1 && remote_version >= 17) {
	  extern int module_id;
	  extern int ignore_errors;
	  if (lp_ignore_errors(module_id) || ignore_errors) {
		  read_int(f);
	  } else {
		  io_error |= read_int(f);
	  }
  }

  if (list_only) {
	  int i;
	  for (i=0;i<flist->count;i++) {
		  list_file_entry(flist->files[i]);
	  }
  }


  if (verbose > 2)
    rprintf(FINFO,"recv_file_list done\n");

  stats.flist_size = stats.total_read - start_read;
  stats.num_files = flist->count;

  return flist;

oom:
    out_of_memory("recv_file_list");
    return NULL; /* not reached */
}


int file_compare(struct file_struct **f1,struct file_struct **f2)
{
	if (!(*f1)->basename && !(*f2)->basename) return 0;
	if (!(*f1)->basename) return -1;
	if (!(*f2)->basename) return 1;
	if ((*f1)->dirname == (*f2)->dirname)
		return u_strcmp((*f1)->basename, (*f2)->basename);
	return u_strcmp(f_name(*f1),f_name(*f2));
}


int flist_find(struct file_list *flist,struct file_struct *f)
{
	int low=0,high=flist->count-1;

	if (flist->count <= 0) return -1;

	while (low != high) {
		int mid = (low+high)/2;
		int ret = file_compare(&flist->files[flist_up(flist, mid)],&f);
		if (ret == 0) return flist_up(flist, mid);
		if (ret > 0) {
			high=mid;
		} else {
			low=mid+1;
		}
	}

	if (file_compare(&flist->files[flist_up(flist,low)],&f) == 0)
		return flist_up(flist,low);
	return -1;
}


/*
 * free up one file
 */
void free_file(struct file_struct *file)
{
	if (!file) return;
	if (file->basename) free(file->basename);
	if (file->link) free(file->link);
	if (file->sum) free(file->sum);
	memset((char *)file, 0, sizeof(*file));
}


/*
 * free up all elements in a flist
 */
void flist_free(struct file_list *flist)
{
	int i;
	for (i=1;i<flist->count;i++) {
		free_file(flist->files[i]);
		free(flist->files[i]);
	}	
	memset((char *)flist->files, 0, sizeof(flist->files[0])*flist->count);
	free(flist->files);
	memset((char *)flist, 0, sizeof(*flist));
	free(flist);
}


/*
 * This routine ensures we don't have any duplicate names in our file list.
 * duplicate names can cause corruption because of the pipelining 
 */
static void clean_flist(struct file_list *flist, int strip_root)
{
	int i;

	if (!flist || flist->count == 0) 
		return;
  
	qsort(flist->files,flist->count,
	      sizeof(flist->files[0]),
	      (int (*)())file_compare);

	for (i=1;i<flist->count;i++) {
		if (flist->files[i]->basename &&
		    flist->files[i-1]->basename &&
		    strcmp(f_name(flist->files[i]),
			   f_name(flist->files[i-1])) == 0) {
			if (verbose > 1 && !am_server)
				rprintf(FINFO,"removing duplicate name %s from file list %d\n",
					f_name(flist->files[i-1]),i-1);
			free_file(flist->files[i]);
		} 
	}

	if (strip_root) {
		/* we need to strip off the root directory in the case
		   of relative paths, but this must be done _after_
		   the sorting phase */
		for (i=0;i<flist->count;i++) {
			if (flist->files[i]->dirname &&
			    flist->files[i]->dirname[0] == '/') {
				memmove(&flist->files[i]->dirname[0],
					&flist->files[i]->dirname[1],
					strlen(flist->files[i]->dirname));
			}
			
			if (flist->files[i]->dirname && 
			    !flist->files[i]->dirname[0]) {
				flist->files[i]->dirname = NULL;
			}
		}
	}


	if (verbose <= 3) return;

	for (i=0;i<flist->count;i++) {
		rprintf(FINFO,"[%d] i=%d %s %s mode=0%o len=%.0f\n",
			getpid(), i, 
			NS(flist->files[i]->dirname),
			NS(flist->files[i]->basename),
			flist->files[i]->mode,
			(double)flist->files[i]->length);
	}
}


/*
 * return the full filename of a flist entry
 */
char *f_name(struct file_struct *f)
{
	static char names[10][MAXPATHLEN];
	static int n;
	char *p = names[n];

	if (!f || !f->basename) return NULL;

	n = (n+1)%10;

	if (f->dirname) {
		strlcpy(p, f->dirname, MAXPATHLEN);
		strlcat(p, "/", MAXPATHLEN);
		strlcat(p, f->basename, MAXPATHLEN);
	} else {
		strlcpy(p, f->basename, MAXPATHLEN);
	}

	return p;
}