Add option to list cluster chains

man/fatcat.1

@@ -76,7 +76,13 @@ be unreadable.
 .RS 4
 This will display information about the given \fBcluster\fP. It will display its address, which
 is the offset of the cluster in the image, and the FAT entries (next cluster, unallocated
-or end of cluster)
+or end of cluster). A list of cluster chains is displayed if \fB-n\fB is used.
+.RE
+
+.PP
+\fB\-n\fP
+.RS 4
+List cluster chains when displaying cluster information.
 .RE
 
 .PP

src/analysis/FatChains.cpp

@@ -306,25 +306,25 @@ void FatChains::displayOrphaned(list<FatChain> orphanedChains)
     cout << endl;
 }
 
-int FatChains::chainSize(int cluster, bool *isContiguous)
+int FatChains::chainSize(int cluster, list<Segment>& segments)
 {
     set<int> visited;
     int length = 0;
     bool stop;
-
-    if (isContiguous != NULL) {
-        *isContiguous = true;
-    }
+    int start = cluster;
 
     do {
         stop = true;
         int currentCluster = cluster;
         visited.insert(cluster);
         length++;
         cluster = system.nextCluster(cluster);
-        if (system.validCluster(cluster) && cluster!=FAT_LAST) {
-            if (currentCluster+1 != cluster && isContiguous != NULL) {
-                *isContiguous = false;
+        if (cluster==FAT_LAST) {
+            segments.push_back(pair(start, currentCluster));
+        } else if (system.validCluster(cluster)) {
+            if (currentCluster+1 != cluster) {
+                segments.push_back(pair(start, currentCluster));
+                start = cluster;
             }
             if (visited.find(cluster) != visited.end()) {
                 cerr << "! Loop detected, " << currentCluster << " points to " << cluster << " that I already met" << endl;

src/analysis/FatChains.h

@@ -14,6 +14,8 @@
 
 using namespace std;
 
+typedef pair<int, int> Segment;
+
 class FatChains : public FatModule
 {
     public:
@@ -55,7 +57,7 @@ class FatChains : public FatModule
         /**
          * Size of a chain in the FAT
          */
-        int chainSize(int cluster, bool *isContiguous);
+        int chainSize(int cluster, list<Segment>& segments);
 
     protected:
         bool saveEntries;

src/fatcat.cpp

@@ -52,6 +52,7 @@ void usage()
     cout << endl;
     cout << "FAT Hacking" << endl;
     cout << "  -@ [cluster]: Get the cluster address and information" << endl;
+    cout << "  -n: enable listing of cluster chains in cluster information" << endl;
     cout << "  -2: analysis & compare the 2 FATs" << endl;
     cout << "  -b [file]: backup the FATs (see -t)" << endl;
     cout << "* -p [file]: restore (patch) the FATs (see -t)" << endl;
@@ -117,6 +118,9 @@ int main(int argc, char *argv[])
     // -@: get the cluster address
     bool address = false;
 
+    // -n: list cluster chains
+    bool showChains = false;
+
     // -k: analysis the chains
     bool chains = false;
 
@@ -158,7 +162,7 @@ int main(int argc, char *argv[])
     OutputFormatType outputFormat = Default;
 
     // Parsing command line
-    while ((index = getopt(argc, argv, "il:L:r:R:s:dc:hx:2@:ob:p:w:v:mt:Sze:O:fk:a:F:")) != -1) {
+    while ((index = getopt(argc, argv, "il:L:r:R:s:dc:hx:2@:nob:p:w:v:mt:Sze:O:fk:a:F:")) != -1) {
         switch (index) {
         case 'a':
             attributesProvided = true;
@@ -202,6 +206,9 @@ int main(int argc, char *argv[])
             address = true;
             cluster = ATOU(optarg);
             break;
+        case 'n':
+            showChains = true;
+            break;
         case 'o':
             chains = true;
             break;
@@ -326,16 +333,27 @@ int main(int argc, char *argv[])
                 int next2 = fat.nextCluster(cluster, 1);
                 printf("FAT1: %u (%08x)\n", next1, next1);
                 printf("FAT2: %u (%08x)\n", next2, next2);
-                bool isContiguous = false;
 
                 FatChains chains(fat);
-                unsigned long long size = chains.chainSize(cluster, &isContiguous);
+                list<Segment> segments;
+                unsigned long long size = chains.chainSize(cluster, segments);
                 printf("Chain size: %llu (%llu / %s)\n", size, size*fat.bytesPerCluster, prettySize(size*fat.bytesPerCluster).c_str());
-                if (isContiguous) {
+                if (segments.size() < 2) {
                     printf("Chain is contiguous\n");
                 } else {
                     printf("Chain is not contiguous\n");
                 }
+
+                if (showChains) {
+                    list<Segment>::iterator it;
+                    int num=1;
+                    for (it=segments.begin(); it != segments.end(); num++,it++) {
+                        int start = it->first;
+                        int end = it->second;
+                        int size = end - start + 1;
+                        printf("Chain %d: %d..%d (%d clusters)\n", num, start, end, size);
+                    }
+                }
             } else if (chains) {
                 FatChains chains(fat);
                 chains.chainsAnalysis();