/***
fusefile - overlay a file path with a concatenation of parts of
- other files, read only.
+ other files.
- Copyright (C) 2019 Ralph Ronnquist
+ Copyright (C) 2019- Ralph Ronnquist
This program is free software: you can redistribute it and/or
modify it under the terms of the GNU General Public License as
#include <unistd.h>
#include <time.h>
#include <errno.h>
+#include <sys/ioctl.h>
+#include <linux/fs.h>
struct Region {
off_t beg;
/**
* Mark the given region as updated, i.e. written to the overlay. The
- * mark region may attach to prior marked regions ro be a new,
+ * mark region may attach to prior marked regions or be a new,
* separate region. If attaching, it causes the prior regions to
* expand and the table adjusted by deleting any regions that become
* fully contained in other regions.
return ( s == n ) && *(range+c) == 0;
}
+static int setup_source(struct Source *p,char *frag) {
+ struct stat filestat;
+ // Open the fragment file rw if possible, else ro
+ range = strrchr( frag, '/' ); // last '/'
+ p->filename = range? strndup( frag, range - frag ) : frag;
+ p->fd = open( p->filename, O_RDWR );
+ int rdonly = 0;
+ if ( p->fd < 0 ) {
+ rdonly = 1;
+ p->fd = open( p->filename, O_RDONLY );
+ }
+ if ( p->fd < 0 ) {
+ perror( p->filename );
+ return 1; // Error return
+ }
+ if ( stat( p->filename, &filestat ) ) {
+ perror( p->filename );
+ return 1;
+ }
+ if ( rdonly ) {
+ fprintf( stderr, "** %s opened read-only\n", p->filename );
+ }
+ p->from = 0;
+ if ( S_ISBLK( filestat.st_mode ) ) {
+ // Block devices report size differently:
+ if ( ioctl( p->fd, BLKGETSIZE64, &filestat.st_size ) < 0 ) {
+ perror( p->filename );
+ }
+#if DEBUG
+ fprintf( stderr, "block device size = %ld\n", filestat.st_size );
+#endif
+ }
+ p->to = filestat.st_size;
+ // Process any range variation
+ if ( range && *(++range) ) {
+ long int a,b;
+ if ( 0 ) {
+ } else if ( RANGE( sscanf( range, "%ld:%ld%n", &a, &b, &c ), 2 )) {
+ p->from = ( a < 0 )? ( p->to + a ) : a;
+ p->to = ( b < 0 )? ( p->to + b ) : b;
+ } else if ( RANGE( sscanf( range, "%ld+%ld%n", &a, &b, &c ), 2 )) {
+ p->from = ( a < 0 )? ( p->to + a ) : a;
+ p->to = ( ( b < 0 )? p->to : p->from ) + b;
+ } else if ( RANGE( sscanf( range, "%ld+%n", &a, &c ), 1 )) {
+ p->from = ( a < 0 )? ( p->to + a ) : a;
+ } else if ( RANGE( sscanf( range, ":%ld%n", &b, &c ), 1 )) {
+ p->to = ( b < 0 )? ( p->to + b ) : b;
+ } else if ( RANGE( sscanf( range, "%ld:%n", &a, &c ), 1 )) {
+ p->from = ( a < 0 )? ( p->to + a ) : a;
+ } else if ( RANGE( sscanf( range, "%ld%n", &a, &c ), 1 )) {
+ if ( a >= 0 ) {
+ p->from = a;
+ } else {
+ p->from = p->to + a;
+ }
+ } else if ( RANGE( sscanf( range, ":%n", &c), 0 ) ) {
+ // to end from start
+ } else {
+ fprintf( stderr, "** BAD RANGE: %s\n", frag );
+ return 1;
+ }
+ }
+ if ( ( filestat.st_mode & S_IFMT ) == S_IFCHR ) {
+ filestat.st_size = p->to; // Pretend size of character device
+ }
+ if ( p->from < 0 ) {
+ p->from = 0;
+ }
+ if ( p->to > filestat.st_size ) {
+ p->to = filestat.st_size;
+ }
+ if ( p->from >= p->to || p->from >= filestat.st_size ) {
+ fprintf( stderr, "** BAD RANGE: %s [%ld:%ld]\n",
+ frag, p->from, p->to );
+ return 1;
+ }
+ p->start = sources.size; // the fusefile position of fragment
+ sources.size += p->to - p->from;
+ return 0;
+}
+
static int setup_sources(char **argv,int i,int n) {
sources.array = calloc( n, sizeof( struct Source ) );
if ( sources.array == 0 ) {
int j = 0;
sources.size = 0;
for ( ; j < n; i++, j++ ) {
- struct stat filestat;
struct Source *p = sources.array + j;
- // Open the fragment file rw if possible, else ro
- range = strrchr( argv[i], '/' ); // last '/'
- p->filename = range? strndup( argv[i], range - argv[i] ) : argv[i];
- p->fd = open( p->filename, O_RDWR );
- int rdonly = 0;
- if ( p->fd < 0 ) {
- rdonly = 1;
- p->fd = open( p->filename, O_RDONLY );
- }
- if ( p->fd < 0 ) {
- perror( p->filename );
- return 1; // Error return
- }
- if ( stat( p->filename, &filestat ) ) {
- perror( p->filename );
- return 1;
- }
- if ( rdonly ) {
- fprintf( stderr, "** %s opened read-only\n", p->filename );
- }
- p->from = 0;
- p->to = filestat.st_size;
- // Process any range variation
- if ( range && *(++range) ) {
- int a,b;
- if ( 0 ) {
- } else if ( RANGE( sscanf( range, "%d:%d%n", &a, &b, &c ), 2 )) {
- p->from = ( a < 0 )? ( p->to + a ) : a;
- p->to = ( b < 0 )? ( p->to + b ) : b;
- } else if ( RANGE( sscanf( range, "%d+%d%n", &a, &b, &c ), 2 )) {
- p->from = ( a < 0 )? ( p->to + a ) : a;
- p->to = ( ( b < 0 )? p->to : p->from ) + b;
- } else if ( RANGE( sscanf( range, "%d+%n", &a, &c ), 1 )) {
- p->from = ( a < 0 )? ( p->to + a ) : a;
- } else if ( RANGE( sscanf( range, ":%d%n", &b, &c ), 1 )) {
- p->to = ( b < 0 )? ( p->to + b ) : b;
- } else if ( RANGE( sscanf( range, "%d:%n", &a, &c ), 1 )) {
- p->from = ( a < 0 )? ( p->to + a ) : a;
- } else if ( RANGE( sscanf( range, "%d%n", &a, &c ), 1 )) {
- if ( a >= 0 ) {
- p->from = a;
- } else {
- p->from = p->to + a;
- }
- } else if ( RANGE( sscanf( range, ":%n", &c), 0 ) ) {
- // to end from start
- } else {
- fprintf( stderr, "** BAD RANGE: %s\n", argv[i] );
- return 1;
- }
- }
- if ( ( filestat.st_mode & S_IFMT ) == S_IFCHR ) {
- filestat.st_size = p->to; // Pretend size of character device
- }
- if ( p->from < 0 ) {
- p->from = 0;
- }
- if ( p->to > filestat.st_size ) {
- p->to = filestat.st_size;
- }
- if ( p->from >= p->to || p->from >= filestat.st_size ) {
- fprintf( stderr, "** BAD RANGE: %s [%ld:%ld]\n",
- argv[i], p->from, p->to );
+ if ( setup_source( p, argv[i] ) ) {
return 1;
}
- p->start = sources.size; // the fusefile position of fragment
- sources.size += p->to - p->from;
#if DEBUG
print_source( p );
#endif
return 0;
}
+#define ENDSOURCE( S ) ( S.start + ( S.to - S.from ) )
+
+/**
+ * Dump the current fragmentation to stdout.
+ */
+static int dump_fragments() {
+ int oly = 0;
+ int src = 0;
+ size_t pos = 0;
+ while ( src < sources.count ) {
+ size_t x = ( oly < overlay.count )?
+ overlay.table[ oly ].beg : sources.size;
+ for ( ; src < sources.count &&
+ ENDSOURCE( sources.array[ src ] ) <= x; src++ ) {
+ // Dump sources.array[src] in full
+ fprintf( stdout, "%s/%ld:%ld\n",
+ sources.array[ src ].filename,
+ pos - sources.array[ src ].start,
+ sources.array[ src ].to );
+ pos = ENDSOURCE( sources.array[ src ] );
+ }
+ if ( sources.array[ src ].start < x ) {
+ // Dump sources.array[src] up to x;
+ fprintf( stdout, "%s/%ld:%ld\n",
+ sources.array[ src ].filename,
+ pos - sources.array[ src ].start,
+ x - sources.array[ src ].start );
+ pos = ENDSOURCE( sources.array[ src ] );
+ }
+ if ( oly < overlay.count ) {
+ fprintf( stdout, "%s/%ld:%ld\n",
+ overlay.source.filename,
+ overlay.table[ oly ].beg,
+ overlay.table[ oly ].end );
+ pos = overlay.table[ oly++ ].end;
+ }
+ for ( ; src < sources.count &&
+ ENDSOURCE( sources.array[ src ] ) <= pos; src++ ) {
+ // Just skip these fragments.
+ }
+ }
+ return( 0 );
+}
+
static struct fuse_operations fusefile_oper = {
.getattr = fusefile_getattr,
+ // NYI .fgetattr = fusefile_fgetattr,
.chmod = fusefile_chmod,
.open = fusefile_open,
.read = fusefile_read,
.write = fusefile_write,
.write_buf = fusefile_write_buf,
.destroy = fusefile_destroy,
+ // NYI .access = fusefile_access,
.flush = fusefile_flush,
.release = fusefile_release,
.fsync = fusefile_fsync,
+ // NYI .ftruncate = fusefile_ftruncate,
.truncate = fusefile_truncate,
//.truncate = fusefile_truncate,
//.release = fusefile_release,
}
}
fuseargc = setup_argv( fuseargc, &argv );
+ if ( strcmp( "-dump", argv[ 1 ] ) == 0 ) {
+ return dump_fragments();
+ }
struct fuse_args args = FUSE_ARGS_INIT( fuseargc, argv );
if ( fuse_parse_cmdline( &args, &mnt, &mt, &fg ) ) {
return 1;