From 0ce28cbfed5d711405dbfd85f7321b824842e47a Mon Sep 17 00:00:00 2001
From: Stef <stef@memberwebs.com>
Date: Sat, 27 Nov 2010 15:50:58 +0000
Subject: Redo raw scrounge so that it's faster.

---
 src/locks.h    |  2 +-
 src/main.c     |  4 +--
 src/misc.c     | 32 ++++++++++---------
 src/scrounge.c | 99 +++++++++++++++++++++++++++++++++++++---------------------
 4 files changed, 84 insertions(+), 53 deletions(-)

(limited to 'src')

diff --git a/src/locks.h b/src/locks.h
index 028225a..3d35b39 100644
--- a/src/locks.h
+++ b/src/locks.h
@@ -32,7 +32,7 @@ typedef struct _drivelocks
 drivelocks;
 
 void addLocationLock(drivelocks* locks, uint64 beg, uint64 end);
-bool checkLocationLock(drivelocks* locks, uint64 sec);
+uint64 checkLocationLock(drivelocks* locks, uint64 sec);
 
 #ifdef _DEBUG
 void dumpLocationLocks(drivelocks* locks);
diff --git a/src/main.c b/src/main.c
index 12eb85e..b0cd31b 100644
--- a/src/main.c
+++ b/src/main.c
@@ -91,9 +91,9 @@ int main(int argc, char* argv[])
   pi.cluster = 8;
 
 #ifdef _WIN32
-  while((ch = getopt(argc, argv, "c:d:hlm:o:sv")) != -1)
+  while((ch = getopt(argc, argv, "c:d:hk:lm:o:sv")) != -1)
 #else
-  while((ch = getopt(argc, argv, "c:hlm:o:sv")) != -1)
+  while((ch = getopt(argc, argv, "c:hk:lm:o:sv")) != -1)
 #endif
   {
     switch(ch)
diff --git a/src/misc.c b/src/misc.c
index 255533f..4163348 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -60,25 +60,27 @@ void addLocationLock(drivelocks* locks, uint64 beg, uint64 end)
 	}
 }
 
-bool checkLocationLock(drivelocks* locks, uint64 sec)
+uint64 checkLocationLock(drivelocks* locks, uint64 sec)
 {
-  uint32 i;
+	uint64 locked;
+	uint32 i;
 
-  if(locks->_locks)
-  {
-  	/* Go through and check for a lock */
-	  for(i = 0; i < locks->_current; i++)
-	  {
-		  if(sec >= locks->_locks[i].beg && 
-			  sec < locks->_locks[i].end)
-		  {
-			  sec = locks->_locks[i].end;
-			  return true;
-		  }
-    }
+	if(locks->_locks)
+	{
+		/* Go through and check for a lock */
+		for(i = 0; i < locks->_current; i++)
+		{
+			if(sec >= locks->_locks[i].beg &&
+			   sec < locks->_locks[i].end)
+			{
+				locked = locks->_locks[i].end - sec;
+				assert(locked != 0);
+				return locked;
+			}
+		}
 	}
 
-	return false;
+	return 0;
 }
 
 #ifdef _DEBUG
diff --git a/src/scrounge.c b/src/scrounge.c
index ad340b0..a5670d7 100644
--- a/src/scrounge.c
+++ b/src/scrounge.c
@@ -611,57 +611,86 @@ void scroungeUsingMFT(partitioninfo* pi)
 
 void scroungeUsingRaw(partitioninfo* pi, uint64 skip)
 {
-  byte buffSec[kSectorSize];
-  fchar_t dir[MAX_PATH + 1];
-  uint64 sec;
-  drivelocks locks;
-  int64 pos;
-  size_t sz;
-  uint32 magic = kNTFS_RecMagic;
-
-  fprintf(stderr, "[Scrounging raw records...]\n");
+	byte *buffer;
+	size_t length;
+	byte *bufsec;
+	fchar_t dir[MAX_PATH + 1];
+	uint64 sec;
+	drivelocks locks;
+	int64 pos;
+	uint64 locked;
+	size_t sz;
+	uint32 magic = kNTFS_RecMagic;
+
+	fprintf(stderr, "[Scrounging raw records...]\n");
 
 	/* Save current directory away */
 	fc_getcwd(dir, MAX_PATH);
 
-  /* Get the locks ready */
-  memset(&locks, 0, sizeof(locks));
-  pi->locks = &locks;
+	/* Get the locks ready */
+	memset(&locks, 0, sizeof(locks));
+	pi->locks = &locks;
+
+	/* The memory buffer */
+	length = kSectorSize * 2048;
+	buffer = malloc(length);
+	if(!buffer)
+		errx(1, "out of memory");
 
 	/* Loop through sectors */
-	for(sec = pi->first + skip; sec < pi->end; sec++)
+	sec = pi->first + skip;
+	while(sec < pi->end)
 	{
-    if(checkLocationLock(&locks, sec))
-      continue;
-
 #ifdef _WIN32
-	fprintf(stderr, "sector: %I64u\r", sec);
+		fprintf(stderr, "sector: %I64u\r", sec);
 #else
-	fprintf(stderr, "sector: %llu\r", (unsigned long long)sec);
+		fprintf(stderr, "sector: %llu\r", (unsigned long long)sec);
 #endif
 
-  	/* Read	the record */
-    pos = SECTOR_TO_BYTES(sec);
-    if(lseek64(pi->device, pos, SEEK_SET) == -1)
-      errx(1, "can't seek device to sector");
+		/* Skip any locked sectors, already read */
+		locked = checkLocationLock(&locks, sec);
+		if(locked > 0)
+		{
+			sec += locked;
+			continue;
+		}
 
-    sz = read(pi->device, buffSec, kSectorSize);
-    if(sz == -1 || sz != kSectorSize)
-    {
-      warn("can't read drive sector");
-      continue;
-    }
+		/* Read a buffer size at this point */
+		pos = SECTOR_TO_BYTES(sec);
+		if(lseek64(pi->device, pos, SEEK_SET) == -1)
+			errx(1, "can't seek device to sector");
 
-		/* Check beginning of sector for the magic signature */
-		if(!memcmp(&magic, &buffSec, sizeof(magic)))
+		sz = read(pi->device, buffer, length);
+		if(sz == -1 || sz < kSectorSize)
 		{
-      /* Process the record */
-      processMFTRecord(pi, sec, 0);
+			warn("can't read drive sector");
+
+			/* Try again and go much slower */
+			if(length != kSectorSize)
+				length = kSectorSize;
+
+			/* Already going slow, skip sector */
+			else
+				++sec;
+
+			continue;
 		}
 
-  	/* Move to right output directory */
-    fc_chdir(dir);
+		/* Now go through the read data */
+		for(bufsec = buffer; bufsec < buffer + sz;
+			bufsec += kSectorSize, ++sec)
+		{
+			/* Check beginning of sector for the magic signature */
+			if(!memcmp(&magic, bufsec, sizeof(magic)))
+			{
+				/* Process the record */
+				processMFTRecord(pi, sec, 0);
+			}
+
+			/* Move to right output directory */
+			fc_chdir(dir);
+		}
 	}
 
-  pi->locks = NULL;
+	pi->locks = NULL;
 }
-- 
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