diff options
Diffstat (limited to 'firmware')
| -rw-r--r-- | firmware/drivers/fat.c | 68 |
1 files changed, 49 insertions, 19 deletions
diff --git a/firmware/drivers/fat.c b/firmware/drivers/fat.c index de579f7603..c97772361e 100644 --- a/firmware/drivers/fat.c +++ b/firmware/drivers/fat.c @@ -296,7 +296,9 @@ void fat_init(void) #endif } -int fat_mount(IF_MV2(int volume,) IF_MD2(int drive,) long startsector) +/* fat_mount_internal is split out of fat_mount() to avoid having both the sector + * buffer used here and the sector buffer used by update_fsinfo() on stack */ +static int fat_mount_internal(IF_MV2(int volume,) IF_MD2(int drive,) long startsector) { #ifndef HAVE_MULTIVOLUME const int volume = 0; @@ -443,6 +445,20 @@ int fat_mount(IF_MV2(int volume,) IF_MD2(int drive,) long startsector) fat_bpb->fsinfo.freecount = BYTES2INT32(buf, FSINFO_FREECOUNT); fat_bpb->fsinfo.nextfree = BYTES2INT32(buf, FSINFO_NEXTFREE); } + return 0; +} + +int fat_mount(IF_MV2(int volume,) IF_MD2(int drive,) long startsector) +{ +#ifndef HAVE_MULTIVOLUME + const int volume = 0; +#endif + struct bpb* fat_bpb = &fat_bpbs[volume]; + int rc; + + rc = fat_mount_internal(IF_MV2(volume,) IF_MD2(drive,) startsector); + + if(rc!=0) return rc; /* calculate freecount if unset */ if ( fat_bpb->fsinfo.freecount == 0xffffffff ) @@ -1101,9 +1117,9 @@ static int write_long_name(struct fat_file* file, unsigned int numentries, const unsigned char* name, const unsigned char* shortname, - bool is_directory) + bool is_directory, + unsigned char *sector_buffer) { - unsigned char buf[SECTOR_SIZE]; unsigned char* entry; unsigned int idx = firstentry % DIR_ENTRIES_PER_SECTOR; unsigned int sector = firstentry / DIR_ENTRIES_PER_SECTOR; @@ -1120,7 +1136,7 @@ static int write_long_name(struct fat_file* file, if (rc<0) return rc * 10 - 1; - rc = fat_readwrite(file, 1, buf, false); + rc = fat_readwrite(file, 1, sector_buffer, false); if (rc<1) return rc * 10 - 2; @@ -1147,25 +1163,25 @@ static int write_long_name(struct fat_file* file, if (rc<0) return rc * 10 - 3; - rc = fat_readwrite(file, 1, buf, true); + rc = fat_readwrite(file, 1, sector_buffer, true); if (rc<1) return rc * 10 - 4; /* read next sector */ - rc = fat_readwrite(file, 1, buf, false); + rc = fat_readwrite(file, 1, sector_buffer, false); if (rc<0) { LDEBUGF("Failed writing new sector: %d\n",rc); return rc * 10 - 5; } if (rc==0) /* end of dir */ - memset(buf, 0, sizeof buf); + memset(sector_buffer, 0, SECTOR_SIZE); sector++; idx = 0; } - entry = buf + idx * DIR_ENTRY_SIZE; + entry = sector_buffer + idx * DIR_ENTRY_SIZE; /* verify this entry is free */ if (entry[0] && entry[0] != 0xe5 ) @@ -1234,7 +1250,7 @@ static int write_long_name(struct fat_file* file, if (rc<0) return rc * 10 - 6; - rc = fat_readwrite(file, 1, buf, true); + rc = fat_readwrite(file, 1, sector_buffer, true); if (rc<1) return rc * 10 - 7; @@ -1411,7 +1427,8 @@ static int add_dir_entry(struct fat_dir* dir, firstentry, sector); rc = write_long_name(&dir->file, firstentry, - entries_needed, name, shortname, is_directory); + entries_needed, name, + shortname, is_directory, buf); if (rc < 0) return rc * 10 - 7; @@ -1690,6 +1707,23 @@ int fat_create_file(const char* name, return rc; } +/* noinline because this is only split out of fat_create_dir to make sure + * the sector buffer doesn't remain on the stack, to avoid nasty stack + * overflows later on (when flush_fat() is called */ +static __attribute__((noinline)) int fat_clear_cluster(int sector, + struct bpb *fat_bpb) +{ + unsigned char buf[SECTOR_SIZE]; + int i,rc; + memset(buf, 0, sizeof buf); + for(i = 0;i < (int)fat_bpb->bpb_secperclus;i++) { + rc = transfer(IF_MV2(fat_bpb,) sector + i, 1, buf, true ); + if (rc < 0) + return rc * 10 - 2; + } + return 0; +} + int fat_create_dir(const char* name, struct fat_dir* newdir, struct fat_dir* dir) @@ -1699,8 +1733,6 @@ int fat_create_dir(const char* name, #else struct bpb* fat_bpb = &fat_bpbs[0]; #endif - unsigned char buf[SECTOR_SIZE]; - int i; long sector; int rc; struct fat_file dummyfile; @@ -1724,13 +1756,11 @@ int fat_create_dir(const char* name, update_fat_entry(IF_MV2(fat_bpb,) newdir->file.firstcluster, FAT_EOF_MARK); /* Clear the entire cluster */ - memset(buf, 0, sizeof buf); sector = cluster2sec(IF_MV2(fat_bpb,) newdir->file.firstcluster); - for(i = 0;i < (int)fat_bpb->bpb_secperclus;i++) { - rc = transfer(IF_MV2(fat_bpb,) sector + i, 1, buf, true ); - if (rc < 0) - return rc * 10 - 2; - } + rc = fat_clear_cluster(sector,fat_bpb); + if (rc < 0) + return rc; + /* Then add the "." entry */ rc = add_dir_entry(newdir, &dummyfile, ".", true, true); @@ -1939,7 +1969,6 @@ int fat_rename(struct fat_file* file, int rc; struct fat_dir olddir; struct fat_file newfile = *file; - unsigned char buf[SECTOR_SIZE]; unsigned char* entry = NULL; unsigned short* clusptr = NULL; unsigned int parentcluster; @@ -1986,6 +2015,7 @@ int fat_rename(struct fat_file* file, /* if renaming a directory, update the .. entry to make sure it points to its parent directory (we don't check if it was a move) */ if(FAT_ATTR_DIRECTORY == attr) { + unsigned char buf[SECTOR_SIZE]; /* open the dir that was renamed, we re-use the olddir struct */ rc = fat_opendir(IF_MV2(file->volume,) &olddir, newfile.firstcluster, NULL); |