Bugfixes: (1) add_dir_entry() always appended new entries, although the code intended to reuse deleted entries. New code reuses deleted entries whenever possible. (2) If the code could not extend the dir to append new entries (FAT16 root dir or disk full), it failed because of (1). (3) Even if reuse had worked, it would never have reused entry 0. (4) Shortname char 0xE5->0x05 replacement to avoid treatment as free entry was done for all chars although it should only be done for the first. The 0x05->0xE5 replacement on read was missing altogether. (5) Obey directory size limit (65536 entries == 2 MB). Improvements: (1) The (undocumented) flags used by WinNT derivates to store the case of a shortname's name and extension part are now supported for reading. (2) smaller code size.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@6332 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 95 insertions, 121 deletions

diff --git a/firmware/drivers/fat.c b/firmware/drivers/fat.c
index 79b9dc0..88467f2 100644
--- a/firmware/drivers/fat.c
+++ b/firmware/drivers/fat.c
@@ -85,6 +85,10 @@
 #define FAT_ATTR_LONG_NAME_MASK (FAT_ATTR_READ_ONLY | FAT_ATTR_HIDDEN | \
                                  FAT_ATTR_SYSTEM | FAT_ATTR_VOLUME_ID | \
                                  FAT_ATTR_DIRECTORY | FAT_ATTR_ARCHIVE )
+                                 
+/* NTRES flags */
+#define FAT_NTRES_LC_NAME    0x08
+#define FAT_NTRES_LC_EXT     0x10
 
 #define FATDIR_NAME          0
 #define FATDIR_ATTR          11
@@ -1235,14 +1239,11 @@ static int add_dir_entry(struct fat_dir* dir,
     struct bpb* fat_bpb = &fat_bpbs[0];
 #endif
     unsigned char buf[SECTOR_SIZE];
-    unsigned char shortname[16];
+    unsigned char shortname[12];
     int rc;
     unsigned int sector;
     bool done = false;
-    bool eof = false;
-    bool last = false;
     int entries_needed, entries_found = 0;
-    int namelen = strlen(name);
     int firstentry;
 
     LDEBUGF( "add_dir_entry(%s,%lx)\n",
@@ -1255,87 +1256,71 @@ static int add_dir_entry(struct fat_dir* dir,
     /* The "." and ".." directory entries must not be long names */
     if(dotdir) {
         int i;
-        strncpy(shortname, name, 16);
-        for(i = strlen(shortname);i < 12;i++)
+        strncpy(shortname, name, 12);
+        for(i = strlen(shortname); i < 12; i++)
             shortname[i] = ' ';
         
         entries_needed = 1;
     } else {
-        /* create dos name */
         rc = create_dos_name(name, shortname);
         if (rc < 0)
             return rc * 10 - 0;
 
         /* one dir entry needed for every 13 bytes of filename,
            plus one entry for the short name */
-        entries_needed = namelen / NAME_BYTES_PER_ENTRY + 1;
-        if (namelen % NAME_BYTES_PER_ENTRY)
-            entries_needed++;
+        entries_needed = (strlen(name) + (NAME_BYTES_PER_ENTRY-1))
+                         / NAME_BYTES_PER_ENTRY + 1;
     }
 
- restart:
-    firstentry = 0;
-
+  restart:
+    firstentry = -1;
+    
     rc = fat_seek(&dir->file, 0);
     if (rc < 0)
         return rc * 10 - 1;
 
-    for (sector=0; !done; sector++)
+    /* step 1: search for free entries and check for duplicate shortname */
+    for (sector = 0; !done; sector++)
     {
         unsigned int i;
 
-        rc = 0;
-        if (!eof) {
-            rc = fat_readwrite(&dir->file, 1, buf, false);
-        }
-        if (rc == 0) {
-            /* eof: add new sector */
-            eof = true;
-
-            memset(buf, 0, sizeof buf);
-            LDEBUGF("Adding new sector to dir\n");
-            rc = fat_seek(&dir->file, sector);
-            if (rc < 0)
-                return rc * 10 - 2;
-
-            /* add sectors (we must clear the whole cluster) */
-            do {
-                rc = fat_readwrite(&dir->file, 1, buf, true);
-                if (rc < 1)
-                    return rc * 10 - 3;
-            } while (dir->file.sectornum < (int)fat_bpb->bpb_secperclus);
-        }
+        rc = fat_readwrite(&dir->file, 1, buf, false);
         if (rc < 0) {
             DEBUGF( "add_dir_entry() - Couldn't read dir"
                     " (error code %d)\n", rc);
-            return rc * 10 - 4;
+            return rc * 10 - 2;
+        }
+
+        if (rc == 0) { /* current end of dir reached */
+            LDEBUGF("End of dir on cluster boundary\n");
+            break;
         }
 
         /* look for free slots */
-        for (i=0; i < DIR_ENTRIES_PER_SECTOR && !done; i++)
+        for (i = 0; i < DIR_ENTRIES_PER_SECTOR; i++)
         {
-            unsigned char firstbyte = buf[i * DIR_ENTRY_SIZE];
-            switch (firstbyte) {
-            case 0: /* end of dir */
-                entries_found = entries_needed;
-                LDEBUGF("Found last entry %d\n", 
+            switch (buf[i * DIR_ENTRY_SIZE]) {
+              case 0:
+                entries_found += DIR_ENTRIES_PER_SECTOR - i;
+                LDEBUGF("Found end of dir %d\n",
                         sector * DIR_ENTRIES_PER_SECTOR + i);
+                i = DIR_ENTRIES_PER_SECTOR - 1;
                 done = true;
                 break;
 
-            case 0xe5: /* free entry */
+              case 0xe5:
                 entries_found++;
                 LDEBUGF("Found free entry %d (%d/%d)\n",
                         sector * DIR_ENTRIES_PER_SECTOR + i,
                         entries_found, entries_needed);
                 break;
 
-            default:
+              default:
                 entries_found = 0;
 
                 /* check that our intended shortname doesn't already exist */
                 if (!strncmp(shortname, buf + i * DIR_ENTRY_SIZE, 12)) {
-                    /* filename exists already. make a new one */
+                    /* shortname exists already, make a new one */
                     randomize_dos_name(shortname);
                     LDEBUGF("Duplicate shortname, changing to %s\n",
                             shortname);
@@ -1345,28 +1330,53 @@ static int add_dir_entry(struct fat_dir* dir,
                 }
                 break;
             }
+            if (firstentry < 0 && (entries_found >= entries_needed))
+                firstentry = sector * DIR_ENTRIES_PER_SECTOR + i + 1
+                             - entries_found;
+        }
+    }
 
-            if (!firstentry && (entries_found == entries_needed)) {
-                firstentry = sector * DIR_ENTRIES_PER_SECTOR + i;
+    /* step 2: extend the dir if necessary */
+    if (firstentry < 0)
+    {
+#ifdef HAVE_FAT16SUPPORT
+        if (dir->file.firstcluster < 0) {
+            LDEBUGF("FAT16 root dir isn't extendable\n");
+            return -3;
+        }
+#endif
+        LDEBUGF("Adding new sector(s) to dir\n");
+        rc = fat_seek(&dir->file, sector);
+        if (rc < 0)
+            return rc * 10 - 4;
+        memset(buf, 0, sizeof buf);
 
-                /* if we're not extending the dir,
-                   we must go back to first free entry */
-                if (done)
-                    last = true;
-                else
-                    firstentry -= (entries_needed - 1);
-            }
+        /* we must clear whole clusters */
+        for (; (entries_found < entries_needed) ||
+               (dir->file.sectornum < (int)fat_bpb->bpb_secperclus); sector++)
+        {
+            if (sector >= (65536/DIR_ENTRIES_PER_SECTOR))
+                return -5; /* dir too large -- FAT specification */
+
+            rc = fat_readwrite(&dir->file, 1, buf, true);
+            if (rc < 1)  /* No more room or something went wrong */
+                return rc * 10 - 6;
+
+            entries_found += DIR_ENTRIES_PER_SECTOR;
         }
+
+        firstentry = sector * DIR_ENTRIES_PER_SECTOR - entries_found;
     }
 
+    /* step 3: add entry */
     sector = firstentry / DIR_ENTRIES_PER_SECTOR;
     LDEBUGF("Adding longname to entry %d in sector %d\n",
             firstentry, sector);
-
-    rc = write_long_name(&dir->file, firstentry, 
+            
+    rc = write_long_name(&dir->file, firstentry,
                          entries_needed, name, shortname, is_directory);
     if (rc < 0)
-        return rc * 10 - 5;
+        return rc * 10 - 7;
 
     /* remember where the shortname dir entry is located */
     file->direntry = firstentry + entries_needed - 1;
@@ -1375,53 +1385,6 @@ static int add_dir_entry(struct fat_dir* dir,
     LDEBUGF("Added new dir entry %d, using %d slots.\n",
             file->direntry, file->direntries);
 
-    /* advance the end-of-dir marker? */
-    if (last)
-    {
-        unsigned int lastentry = firstentry + entries_needed;
-
-        LDEBUGF("Updating end-of-dir entry %d\n",lastentry);
-
-        if (lastentry % DIR_ENTRIES_PER_SECTOR)
-        {
-            int idx = (lastentry % DIR_ENTRIES_PER_SECTOR) * DIR_ENTRY_SIZE;
-
-            rc = fat_seek(&dir->file, lastentry / DIR_ENTRIES_PER_SECTOR);
-            if (rc < 0)
-                return rc * 10 - 6;
-
-            rc = fat_readwrite(&dir->file, 1, buf, false);
-            if (rc < 1)
-                return rc * 10 - 7;
-
-            /* clear last entry */
-            buf[idx] = 0;
-
-            rc = fat_seek(&dir->file, lastentry / DIR_ENTRIES_PER_SECTOR);
-            if (rc < 0)
-                return rc * 10 - 8;
-            
-            /* we must clear entire last cluster */
-            do {
-                rc = fat_readwrite(&dir->file, 1, buf, true);
-                if (rc < 1)
-                    return rc * 10 - 9;
-                memset(buf, 0, sizeof buf);
-            } while (dir->file.sectornum < (int)fat_bpb->bpb_secperclus);
-        }
-        else
-        {
-            /* add a new sector/cluster for last entry */
-            memset(buf, 0, sizeof buf);
-            do {
-                rc = fat_readwrite(&dir->file, 1, buf, true);
-                if (rc < 1)
-                    return rc * 10 - 9; /* Same error code as above, can't be
-                                           more than -9 */
-            } while (dir->file.sectornum < (int)fat_bpb->bpb_secperclus);
-        }
-    }
-
     return 0;
 }
 
@@ -1429,10 +1392,6 @@ unsigned char char2dos(unsigned char c)
 {
     switch(c)
     {
-        case 0xe5: /* Special kanji character */
-            c = 0x05;
-            break;
-
         case 0x22:
         case 0x2a:
         case 0x2b:
@@ -1448,16 +1407,15 @@ unsigned char char2dos(unsigned char c)
         case 0x5c:
         case 0x5d:
         case 0x7c:
-            /* Illegal name, replace */
+            /* Illegal char, replace */
             c = '_';
             break;
                 
         default:
             if(c <= 0x20)
-            {
-                /* Illegal name, remove */
-                c = 0;
-            }
+                c = 0;   /* Illegal char, remove */
+            else
+                c = toupper(c);
             break;
     }
     return c;
@@ -1478,13 +1436,16 @@ static int create_dos_name(const unsigned char *name, unsigned char *newname)
     {
         unsigned char c = char2dos(*name);
         if (c)
-            newname[i++] = toupper(c);
+            newname[i++] = c;
     }
 
     /* Pad both name and extension */
     while (i < 11)
         newname[i++] = ' ';
 
+    if (newname[0] == 0xe5) /* Special kanji character */
+        newname[0] = 0x05;
+
     if (ext)
     {   /* Extension part */
         ext++;
@@ -1492,7 +1453,7 @@ static int create_dos_name(const unsigned char *name, unsigned char *newname)
         {
             unsigned char c = char2dos(*ext);
             if (c)
-                newname[i++] = toupper(c);
+                newname[i++] = c;
         }
     }
     return 0;
@@ -1580,6 +1541,9 @@ static int update_short_entry( struct fat_file* file, long size, int attr )
 static int parse_direntry(struct fat_direntry *de, const unsigned char *buf)
 {
     int i=0,j=0;
+    unsigned char c;
+    bool lowercase;
+
     memset(de, 0, sizeof(struct fat_direntry));
     de->attr = buf[FATDIR_ATTR];
     de->crttimetenth = buf[FATDIR_CRTTIMETENTH];
@@ -1592,14 +1556,24 @@ static int parse_direntry(struct fat_direntry *de, const unsigned char *buf)
         ((long)(unsigned)BYTES2INT16(buf,FATDIR_FSTCLUSHI) << 16);
     /* The double cast is to prevent a sign-extension to be done on CalmRISC16.
        (the result of the shift is always considered signed) */
-
+       
     /* fix the name */
-    for (i=0; (i<8) && (buf[FATDIR_NAME+i] != ' '); i++)
-        de->name[j++] = buf[FATDIR_NAME+i];
-    if ( buf[FATDIR_NAME+8] != ' ' ) {
+    lowercase = (buf[FATDIR_NTRES] & FAT_NTRES_LC_NAME);
+    c = buf[FATDIR_NAME];
+    if (c == 0x05)  /* special kanji char */
+        c = 0xe5;
+    i = 0;
+    while (c != ' ') {
+        de->name[j++] = lowercase ? tolower(c) : c;
+        if (++i >= 8)
+            break;
+        c = buf[FATDIR_NAME+i];
+    }
+    if (buf[FATDIR_NAME+8] != ' ') {
+        lowercase = (buf[FATDIR_NTRES] & FAT_NTRES_LC_EXT);
         de->name[j++] = '.';
-        for (i=8; (i<11) && (buf[FATDIR_NAME+i] != ' '); i++)
-            de->name[j++] = buf[FATDIR_NAME+i];
+        for (i = 8; (i < 11) && ((c = buf[FATDIR_NAME+i]) != ' '); i++)
+            de->name[j++] = lowercase ? tolower(c) : c;
     }
     return 1;
 }