From d45b7f29190174659d597b966e09662afd820bad Mon Sep 17 00:00:00 2001
From: Ralph Ronnquist <ralph.ronnquist@gmail.com>
Date: Sun, 25 Jun 2023 13:35:35 +1000
Subject: [PATCH] Minor refactoring.

---
 fusefile.c | 137 ++++++++++++++++++++++++++++-------------------------
 1 file changed, 73 insertions(+), 64 deletions(-)

diff --git a/fusefile.c b/fusefile.c
index d8729b9..f886287 100644
--- a/fusefile.c
+++ b/fusefile.c
@@ -290,6 +290,78 @@ static int RANGE(int s,int n ) {
     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;
+    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", 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 ) {
@@ -299,71 +371,8 @@ static int setup_sources(char **argv,int i,int n) {
     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
-- 
2.39.2