diff options
| -rw-r--r-- | docs/keep_data_small.txt | 68 | ||||
| -rw-r--r-- | util-linux/mkfs_minix.c | 368 |
2 files changed, 242 insertions, 194 deletions
diff --git a/docs/keep_data_small.txt b/docs/keep_data_small.txt index ec13b4d..5137dff 100644 --- a/docs/keep_data_small.txt +++ b/docs/keep_data_small.txt @@ -1,4 +1,4 @@ - Keeping data small + Keeping data small When many applets are compiled into busybox, all rw data and bss for each applet are concatenated. Including those from libc, @@ -10,6 +10,11 @@ On nommu it's probably bites the most, actually using real RAM for rwdata and bss. On i386, bss is lazily allocated by COWed zero pages. Not sure about rwdata - also COW? +In order to keep bbox NOMMU and small-mem systems friendly +we should avoid large global data in our applets, and should +minimize usage of libc functions which implicitly use +such structures in libc. + Small experiment measures "parasitic" bbox memory consumption. Here we start 1000 "busybox sleep 10" in parallel. bbox binary is practically allyesconfig static one, @@ -34,14 +39,10 @@ bash-3.2# nmeter '%t %c %b %m %p %[pn]' 23:17:43 .......... 0 0 168M 0 147 This requires 55M of memory. Thus 1 trivial busybox applet -takes 55k of userspace memory (nmeter doesn't account for kernel-side -allocations). Definitely can be improved. +takes 55k of memory. -Thus we should avoid large global data in our applets, -and should minimize usage of libc functions which implicitly use -such structures in libc. - Example 1 + Example 1 One example how to reduce global data usage is in archival/libunarchive/decompress_unzip.c: @@ -57,12 +58,15 @@ archival/libunarchive/decompress_unzip.c: #define STATE_IN_BSS 0 #define STATE_IN_MALLOC 1 +(see the rest of the file to get the idea) + This example completely eliminates globals in that module. Required memory is allocated in inflate_gunzip() [its main module] and then passed down to all subroutines which need to access 'globals' as a parameter. - Example 2 + + Example 2 In case you don't want to pass this additional parameter everywhere, take a look at archival/gzip.c. Here all global data is replaced by @@ -70,7 +74,7 @@ single global pointer (ptr_to_globals) to allocated storage. In order to not duplicate ptr_to_globals in every applet, you can reuse single common one. It is defined in libbb/messages.c -as struct globals *ptr_to_globals, but the struct globals is +as struct globals *const ptr_to_globals, but the struct globals is NOT defined in libbb.h. You first define your own struct: struct globals { int a; char buf[1000]; }; @@ -79,13 +83,45 @@ and then declare that ptr_to_globals is a pointer to it: #define G (*ptr_to_globals) -Linker magic ensures that these two merge into single pointer object. -Now initialize it in <applet>_main(): +ptr_to_globals is declared as constant pointer. +This helps gcc understand that it won't change, resulting in noticeably +smaller code. In order to assign it, use PTR_TO_GLOBALS macro: + + PTR_TO_GLOBALS = xzalloc(sizeof(G)); + +Typically it is done in <applet>_main(). + +Now you can reference "globals" by G.a, G.buf and so on, in any function. + + + bb_common_bufsiz1 + +There is one big common buffer in bss - bb_common_bufsiz1. It is a much +earlier mechanism to reduce bss usage. Each applet can use it for +its needs. Library functions are prohibited from using it. + +'G.' trick can be done using bb_common_bufsiz1 instead of malloced buffer: + +#define G (*(struct globals*)&bb_common_bufsiz1) + +Be careful, though, and use it only if +sizeof(struct globals) <= sizeof(bb_common_bufsiz1). + + + Drawbacks + +You have to initialize it by hand. xzalloc() can be helpful in clearing +allocated storage to 0, but anything more must be done by hand. + +All global variables are prefixed by 'G.' now. If this makes code +less readable, use #defines: + +#define dev_fd (G.dev_fd) +#define sector (G.sector) - ptr_to_globals = xzalloc(sizeof(G)); -and you can reference "globals" by G.a, G.buf and so on, in any function. + Word of caution -The drawback is that now you have to initialize it by hand. xzalloc() -can be helpful in clearing allocated storage to 0, but anything more -must be done by hand. +If applet doesn't use much of global data, converting it to using +one of above methods is not worth resulting code obfuscation. +If you have less that ~300 bytes of global data - don't bother. diff --git a/util-linux/mkfs_minix.c b/util-linux/mkfs_minix.c index e9ac935..2ba9233 100644 --- a/util-linux/mkfs_minix.c +++ b/util-linux/mkfs_minix.c @@ -85,42 +85,49 @@ enum { TEST_BUFFER_BLOCKS = 16, }; -#if ENABLE_FEATURE_MINIX2 -static int version2; -#else +#if !ENABLE_FEATURE_MINIX2 enum { version2 = 0 }; #endif -static char *device_name; -static int dev_fd = -1; -static uint32_t total_blocks; -static int badblocks; -/* default (changed to 30, per Linus's suggestion, Sun Nov 21 08:05:07 1993) */ -static int namelen = 30; -static int dirsize = 32; -static int magic = MINIX1_SUPER_MAGIC2; +struct globals { -static char root_block[BLOCK_SIZE]; -static char super_block_buffer[BLOCK_SIZE]; -static char boot_block_buffer[512]; -static char *inode_buffer; + int dev_fd; -static char *inode_map; -static char *zone_map; +#if ENABLE_FEATURE_MINIX2 + int version2; +#define version2 G.version2 +#endif + char *device_name; + uint32_t total_blocks; + int badblocks; + int namelen; + int dirsize; + int magic; + char *inode_buffer; + char *inode_map; + char *zone_map; + int used_good_blocks; + unsigned long req_nr_inodes; + unsigned currently_testing; + + + char root_block[BLOCK_SIZE]; + char super_block_buffer[BLOCK_SIZE]; + char boot_block_buffer[512]; + unsigned short good_blocks_table[MAX_GOOD_BLOCKS]; +}; -static int used_good_blocks; -static unsigned short good_blocks_table[MAX_GOOD_BLOCKS]; -static unsigned long req_nr_inodes; +#define G (*ptr_to_globals) static ATTRIBUTE_ALWAYS_INLINE unsigned div_roundup(unsigned size, unsigned n) { return (size + n-1) / n; } -#define INODE_BUF1 (((struct minix1_inode*)inode_buffer) - 1) -#define INODE_BUF2 (((struct minix2_inode*)inode_buffer) - 1) +#define INODE_BUF1 (((struct minix1_inode*)G.inode_buffer) - 1) +#define INODE_BUF2 (((struct minix2_inode*)G.inode_buffer) - 1) -#define SB (*(struct minix_super_block*)super_block_buffer) +#define SB (*(struct minix_super_block*)G.super_block_buffer) #define SB_INODES (SB.s_ninodes) #define SB_IMAPS (SB.s_imap_blocks) @@ -160,13 +167,13 @@ static void minix_clrbit(char *a, unsigned i) } /* Note: do not assume 0/1, it is 0/nonzero */ -#define zone_in_use(x) minix_bit(zone_map,(x)-SB_FIRSTZONE+1) -/*#define inode_in_use(x) minix_bit(inode_map,(x))*/ +#define zone_in_use(x) minix_bit(G.zone_map,(x)-SB_FIRSTZONE+1) +/*#define inode_in_use(x) minix_bit(G.inode_map,(x))*/ -#define mark_inode(x) minix_setbit(inode_map,(x)) -#define unmark_inode(x) minix_clrbit(inode_map,(x)) -#define mark_zone(x) minix_setbit(zone_map,(x)-SB_FIRSTZONE+1) -#define unmark_zone(x) minix_clrbit(zone_map,(x)-SB_FIRSTZONE+1) +#define mark_inode(x) minix_setbit(G.inode_map,(x)) +#define unmark_inode(x) minix_clrbit(G.inode_map,(x)) +#define mark_zone(x) minix_setbit(G.zone_map,(x)-SB_FIRSTZONE+1) +#define unmark_zone(x) minix_clrbit(G.zone_map,(x)-SB_FIRSTZONE+1) #ifndef BLKGETSIZE # define BLKGETSIZE _IO(0x12,96) /* return device size */ @@ -227,51 +234,51 @@ static void write_tables(void) SB.s_state &= ~MINIX_ERROR_FS; msg_eol = "seek to 0 failed"; - xlseek(dev_fd, 0, SEEK_SET); + xlseek(G.dev_fd, 0, SEEK_SET); msg_eol = "cannot clear boot sector"; - xwrite(dev_fd, boot_block_buffer, 512); + xwrite(G.dev_fd, G.boot_block_buffer, 512); msg_eol = "seek to BLOCK_SIZE failed"; - xlseek(dev_fd, BLOCK_SIZE, SEEK_SET); + xlseek(G.dev_fd, BLOCK_SIZE, SEEK_SET); msg_eol = "cannot write superblock"; - xwrite(dev_fd, super_block_buffer, BLOCK_SIZE); + xwrite(G.dev_fd, G.super_block_buffer, BLOCK_SIZE); msg_eol = "cannot write inode map"; - xwrite(dev_fd, inode_map, SB_IMAPS * BLOCK_SIZE); + xwrite(G.dev_fd, G.inode_map, SB_IMAPS * BLOCK_SIZE); msg_eol = "cannot write zone map"; - xwrite(dev_fd, zone_map, SB_ZMAPS * BLOCK_SIZE); + xwrite(G.dev_fd, G.zone_map, SB_ZMAPS * BLOCK_SIZE); msg_eol = "cannot write inodes"; - xwrite(dev_fd, inode_buffer, INODE_BUFFER_SIZE); + xwrite(G.dev_fd, G.inode_buffer, INODE_BUFFER_SIZE); msg_eol = "\n"; } static void write_block(int blk, char *buffer) { - xlseek(dev_fd, blk * BLOCK_SIZE, SEEK_SET); - xwrite(dev_fd, buffer, BLOCK_SIZE); + xlseek(G.dev_fd, blk * BLOCK_SIZE, SEEK_SET); + xwrite(G.dev_fd, buffer, BLOCK_SIZE); } static int get_free_block(void) { int blk; - if (used_good_blocks + 1 >= MAX_GOOD_BLOCKS) + if (G.used_good_blocks + 1 >= MAX_GOOD_BLOCKS) bb_error_msg_and_die("too many bad blocks"); - if (used_good_blocks) - blk = good_blocks_table[used_good_blocks - 1] + 1; + if (G.used_good_blocks) + blk = G.good_blocks_table[G.used_good_blocks - 1] + 1; else blk = SB_FIRSTZONE; while (blk < SB_ZONES && zone_in_use(blk)) blk++; if (blk >= SB_ZONES) bb_error_msg_and_die("not enough good blocks"); - good_blocks_table[used_good_blocks] = blk; - used_good_blocks++; + G.good_blocks_table[G.used_good_blocks] = blk; + G.used_good_blocks++; return blk; } @@ -279,8 +286,8 @@ static void mark_good_blocks(void) { int blk; - for (blk = 0; blk < used_good_blocks; blk++) - mark_zone(good_blocks_table[blk]); + for (blk = 0; blk < G.used_good_blocks; blk++) + mark_zone(G.good_blocks_table[blk]); } static int next(int zone) @@ -303,7 +310,7 @@ static void make_bad_inode(void) #define NEXT_BAD (zone = next(zone)) - if (!badblocks) + if (!G.badblocks) return; mark_inode(MINIX_BAD_INO); inode->i_nlinks = 1; @@ -311,7 +318,7 @@ static void make_bad_inode(void) /* it's harder to check for bugs then - diff isn't helpful :(... */ inode->i_time = CUR_TIME; inode->i_mode = S_IFREG + 0000; - inode->i_size = badblocks * BLOCK_SIZE; + inode->i_size = G.badblocks * BLOCK_SIZE; zone = next(0); for (i = 0; i < 7; i++) { inode->i_zone[i] = zone; @@ -354,13 +361,13 @@ static void make_bad_inode2(void) unsigned long ind_block[BLOCK_SIZE >> 2]; unsigned long dind_block[BLOCK_SIZE >> 2]; - if (!badblocks) + if (!G.badblocks) return; mark_inode(MINIX_BAD_INO); inode->i_nlinks = 1; inode->i_atime = inode->i_mtime = inode->i_ctime = CUR_TIME; inode->i_mode = S_IFREG + 0000; - inode->i_size = badblocks * BLOCK_SIZE; + inode->i_size = G.badblocks * BLOCK_SIZE; zone = next(0); for (i = 0; i < 7; i++) { inode->i_zone[i] = zone; @@ -406,18 +413,18 @@ static void make_root_inode(void) inode->i_zone[0] = get_free_block(); inode->i_nlinks = 2; inode->i_time = CUR_TIME; - if (badblocks) - inode->i_size = 3 * dirsize; + if (G.badblocks) + inode->i_size = 3 * G.dirsize; else { - root_block[2 * dirsize] = '\0'; - root_block[2 * dirsize + 1] = '\0'; - inode->i_size = 2 * dirsize; + G.root_block[2 * G.dirsize] = '\0'; + G.root_block[2 * G.dirsize + 1] = '\0'; + inode->i_size = 2 * G.dirsize; } inode->i_mode = S_IFDIR + 0755; inode->i_uid = GETUID; if (inode->i_uid) inode->i_gid = GETGID; - write_block(inode->i_zone[0], root_block); + write_block(inode->i_zone[0], G.root_block); } #if ENABLE_FEATURE_MINIX2 @@ -429,94 +436,23 @@ static void make_root_inode2(void) inode->i_zone[0] = get_free_block(); inode->i_nlinks = 2; inode->i_atime = inode->i_mtime = inode->i_ctime = CUR_TIME; - if (badblocks) - inode->i_size = 3 * dirsize; + if (G.badblocks) + inode->i_size = 3 * G.dirsize; else { - root_block[2 * dirsize] = '\0'; - root_block[2 * dirsize + 1] = '\0'; - inode->i_size = 2 * dirsize; + G.root_block[2 * G.dirsize] = '\0'; + G.root_block[2 * G.dirsize + 1] = '\0'; + inode->i_size = 2 * G.dirsize; } inode->i_mode = S_IFDIR + 0755; inode->i_uid = GETUID; if (inode->i_uid) inode->i_gid = GETGID; - write_block(inode->i_zone[0], root_block); + write_block(inode->i_zone[0], G.root_block); } #else void make_root_inode2(void); #endif -static void setup_tables(void) -{ - unsigned long inodes; - unsigned norm_firstzone; - unsigned sb_zmaps; - unsigned i; - - memset(super_block_buffer, 0, BLOCK_SIZE); - memset(boot_block_buffer, 0, 512); - SB_MAGIC = magic; - SB_ZONE_SIZE = 0; - SB_MAXSIZE = version2 ? 0x7fffffff : (7 + 512 + 512 * 512) * 1024; - if (version2) - SB.s_zones = total_blocks; - else - SB.s_nzones = total_blocks; - - /* some magic nrs: 1 inode / 3 blocks */ - if (req_nr_inodes == 0) - inodes = total_blocks / 3; - else - inodes = req_nr_inodes; - /* Round up inode count to fill block size */ - if (version2) - inodes = (inodes + MINIX2_INODES_PER_BLOCK - 1) & - ~(MINIX2_INODES_PER_BLOCK - 1); - else - inodes = (inodes + MINIX1_INODES_PER_BLOCK - 1) & - ~(MINIX1_INODES_PER_BLOCK - 1); - if (inodes > 65535) - inodes = 65535; - SB_INODES = inodes; - SB_IMAPS = div_roundup(SB_INODES + 1, BITS_PER_BLOCK); - - /* Real bad hack but overwise mkfs.minix can be thrown - * in infinite loop... - * try: - * dd if=/dev/zero of=test.fs count=10 bs=1024 - * mkfs.minix -i 200 test.fs - */ - /* This code is not insane: NORM_FIRSTZONE is not a constant, - * it is calculated from SB_INODES, SB_IMAPS and SB_ZMAPS */ - i = 999; - SB_ZMAPS = 0; - do { - norm_firstzone = NORM_FIRSTZONE; - sb_zmaps = div_roundup(total_blocks - norm_firstzone + 1, BITS_PER_BLOCK); - if (SB_ZMAPS == sb_zmaps) goto got_it; - SB_ZMAPS = sb_zmaps; - /* new SB_ZMAPS, need to recalc NORM_FIRSTZONE */ - } while (--i); - bb_error_msg_and_die("incompatible size/inode count, try different -i N"); - got_it: - - SB_FIRSTZONE = norm_firstzone; - inode_map = xmalloc(SB_IMAPS * BLOCK_SIZE); - zone_map = xmalloc(SB_ZMAPS * BLOCK_SIZE); - memset(inode_map, 0xff, SB_IMAPS * BLOCK_SIZE); - memset(zone_map, 0xff, SB_ZMAPS * BLOCK_SIZE); - for (i = SB_FIRSTZONE; i < SB_ZONES; i++) - unmark_zone(i); - for (i = MINIX_ROOT_INO; i <= SB_INODES; i++) - unmark_inode(i); - inode_buffer = xzalloc(INODE_BUFFER_SIZE); - printf("%ld inodes\n", (long)SB_INODES); - printf("%ld blocks\n", (long)SB_ZONES); - printf("Firstdatazone=%ld (%ld)\n", (long)SB_FIRSTZONE, (long)norm_firstzone); - printf("Zonesize=%d\n", BLOCK_SIZE << SB_ZONE_SIZE); - printf("Maxsize=%ld\n", (long)SB_MAXSIZE); -} - /* * Perform a test of a block; return the number of * blocks readable. @@ -527,11 +463,11 @@ static size_t do_check(char *buffer, size_t try, unsigned current_block) /* Seek to the correct loc. */ msg_eol = "seek failed during testing of blocks"; - xlseek(dev_fd, current_block * BLOCK_SIZE, SEEK_SET); + xlseek(G.dev_fd, current_block * BLOCK_SIZE, SEEK_SET); msg_eol = "\n"; /* Try the read */ - got = read(dev_fd, buffer, try * BLOCK_SIZE); + got = read(G.dev_fd, buffer, try * BLOCK_SIZE); if (got < 0) got = 0; try = ((size_t)got) / BLOCK_SIZE; @@ -541,17 +477,15 @@ static size_t do_check(char *buffer, size_t try, unsigned current_block) return try; } -static unsigned currently_testing; - static void alarm_intr(int alnum) { - if (currently_testing >= SB_ZONES) + if (G.currently_testing >= SB_ZONES) return; signal(SIGALRM, alarm_intr); alarm(5); - if (!currently_testing) + if (!G.currently_testing) return; - printf("%d ...", currently_testing); + printf("%d ...", G.currently_testing); fflush(stdout); } @@ -561,28 +495,29 @@ static void check_blocks(void) /* buffer[] was the biggest static in entire bbox */ char *buffer = xmalloc(BLOCK_SIZE * TEST_BUFFER_BLOCKS); - currently_testing = 0; + G.currently_testing = 0; signal(SIGALRM, alarm_intr); alarm(5); - while (currently_testing < SB_ZONES) { + while (G.currently_testing < SB_ZONES) { msg_eol = "seek failed in check_blocks"; - xlseek(dev_fd, currently_testing * BLOCK_SIZE, SEEK_SET); + xlseek(G.dev_fd, G.currently_testing * BLOCK_SIZE, SEEK_SET); msg_eol = "\n"; try = TEST_BUFFER_BLOCKS; - if (currently_testing + try > SB_ZONES) - try = SB_ZONES - currently_testing; - got = do_check(buffer, try, currently_testing); - currently_testing += got; + if (G.currently_testing + try > SB_ZONES) + try = SB_ZONES - G.currently_testing; + got = do_check(buffer, try, G.currently_testing); + G.currently_testing += got; if (got == try) continue; - if (currently_testing < SB_FIRSTZONE) + if (G.currently_testing < SB_FIRSTZONE) bb_error_msg_and_die("bad blocks before data-area: cannot make fs"); - mark_zone(currently_testing); - badblocks++; - currently_testing++; + mark_zone(G.currently_testing); + G.badblocks++; + G.currently_testing++; } + alarm(0); free(buffer); - printf("%d bad block(s)\n", badblocks); + printf("%d bad block(s)\n", G.badblocks); } static void get_list_blocks(char *filename) @@ -594,9 +529,80 @@ static void get_list_blocks(char *filename) while (!feof(listfile)) { fscanf(listfile, "%ld\n", &blockno); mark_zone(blockno); - badblocks++; + G.badblocks++; } - printf("%d bad block(s)\n", badblocks); + printf("%d bad block(s)\n", G.badblocks); +} + +static void setup_tables(void) +{ + unsigned long inodes; + unsigned norm_firstzone; + unsigned sb_zmaps; + unsigned i; + + /* memset(G.super_block_buffer, 0, BLOCK_SIZE); */ + /* memset(G.boot_block_buffer, 0, 512); */ + SB_MAGIC = G.magic; + SB_ZONE_SIZE = 0; + SB_MAXSIZE = version2 ? 0x7fffffff : (7 + 512 + 512 * 512) * 1024; + if (version2) + SB.s_zones = G.total_blocks; + else + SB.s_nzones = G.total_blocks; + + /* some magic nrs: 1 inode / 3 blocks */ + if (G.req_nr_inodes == 0) + inodes = G.total_blocks / 3; + else + inodes = G.req_nr_inodes; + /* Round up inode count to fill block size */ + if (version2) + inodes = (inodes + MINIX2_INODES_PER_BLOCK - 1) & + ~(MINIX2_INODES_PER_BLOCK - 1); + else + inodes = (inodes + MINIX1_INODES_PER_BLOCK - 1) & + ~(MINIX1_INODES_PER_BLOCK - 1); + if (inodes > 65535) + inodes = 65535; + SB_INODES = inodes; + SB_IMAPS = div_roundup(SB_INODES + 1, BITS_PER_BLOCK); + + /* Real bad hack but overwise mkfs.minix can be thrown + * in infinite loop... + * try: + * dd if=/dev/zero of=test.fs count=10 bs=1024 + * mkfs.minix -i 200 test.fs + */ + /* This code is not insane: NORM_FIRSTZONE is not a constant, + * it is calculated from SB_INODES, SB_IMAPS and SB_ZMAPS */ + i = 999; + SB_ZMAPS = 0; + do { + norm_firstzone = NORM_FIRSTZONE; + sb_zmaps = div_roundup(G.total_blocks - norm_firstzone + 1, BITS_PER_BLOCK); + if (SB_ZMAPS == sb_zmaps) goto got_it; + SB_ZMAPS = sb_zmaps; + /* new SB_ZMAPS, need to recalc NORM_FIRSTZONE */ + } while (--i); + bb_error_msg_and_die("incompatible size/inode count, try different -i N"); + got_it: + + SB_FIRSTZONE = norm_firstzone; + G.inode_map = xmalloc(SB_IMAPS * BLOCK_SIZE); + G.zone_map = xmalloc(SB_ZMAPS * BLOCK_SIZE); + memset(G.inode_map, 0xff, SB_IMAPS * BLOCK_SIZE); + memset(G.zone_map, 0xff, SB_ZMAPS * BLOCK_SIZE); + for (i = SB_FIRSTZONE; i < SB_ZONES; i++) + unmark_zone(i); + for (i = MINIX_ROOT_INO; i <= SB_INODES; i++) + unmark_inode(i); + G.inode_buffer = xzalloc(INODE_BUFFER_SIZE); + printf("%ld inodes\n", (long)SB_INODES); + printf("%ld blocks\n", (long)SB_ZONES); + printf("Firstdatazone=%ld (%ld)\n", (long)SB_FIRSTZONE, (long)norm_firstzone); + printf("Zonesize=%d\n", BLOCK_SIZE << SB_ZONE_SIZE); + printf("Maxsize=%ld\n", (long)SB_MAXSIZE); } int mkfs_minix_main(int argc, char **argv); @@ -609,6 +615,12 @@ int mkfs_minix_main(int argc, char **argv) char *str_i, *str_n; char *listfile = NULL; + PTR_TO_GLOBALS = xzalloc(sizeof(G)); +/* default (changed to 30, per Linus's suggestion, Sun Nov 21 08:05:07 1993) */ + G.namelen = 30; + G.dirsize = 32; + G.magic = MINIX1_SUPER_MAGIC2; + if (INODE_SIZE1 * MINIX1_INODES_PER_BLOCK != BLOCK_SIZE) bb_error_msg_and_die("bad inode size"); #if ENABLE_FEATURE_MINIX2 @@ -619,14 +631,14 @@ int mkfs_minix_main(int argc, char **argv) opt = getopt32(argc, argv, "ci:l:n:v", &str_i, &listfile, &str_n); argv += optind; //if (opt & 1) -c - if (opt & 2) req_nr_inodes = xatoul(str_i); // -i + if (opt & 2) G.req_nr_inodes = xatoul(str_i); // -i //if (opt & 4) -l if (opt & 8) { // -n - namelen = xatoi_u(str_n); - if (namelen == 14) magic = MINIX1_SUPER_MAGIC; - else if (namelen == 30) magic = MINIX1_SUPER_MAGIC2; + G.namelen = xatoi_u(str_n); + if (G.namelen == 14) G.magic = MINIX1_SUPER_MAGIC; + else if (G.namelen == 30) G.magic = MINIX1_SUPER_MAGIC2; else bb_show_usage(); - dirsize = namelen + 2; + G.dirsize = G.namelen + 2; } if (opt & 0x10) { // -v #if ENABLE_FEATURE_MINIX2 @@ -636,34 +648,34 @@ int mkfs_minix_main(int argc, char **argv) #endif } - device_name = *argv++; - if (!device_name) + G.device_name = *argv++; + if (!G.device_name) bb_show_usage(); if (*argv) - total_blocks = xatou32(*argv); + G.total_blocks = xatou32(*argv); else - total_blocks = get_size(device_name) / 1024; + G.total_blocks = get_size(G.device_name) / 1024; - if (total_blocks < 10) + if (G.total_blocks < 10) bb_error_msg_and_die("must have at least 10 blocks"); if (version2) { - magic = MINIX2_SUPER_MAGIC2; - if (namelen == 14) - magic = MINIX2_SUPER_MAGIC; - } else if (total_blocks > 65535) - total_blocks = 65535; + G.magic = MINIX2_SUPER_MAGIC2; + if (G.namelen == 14) + G.magic = MINIX2_SUPER_MAGIC; + } else if (G.total_blocks > 65535) + G.total_blocks = 65535; /* Check if it is mounted */ - mp = find_mount_point(device_name, NULL); - if (mp && strcmp(device_name, mp->mnt_fsname) == 0) + mp = find_mount_point(G.device_name, NULL); + if (mp && strcmp(G.device_name, mp->mnt_fsname) == 0) bb_error_msg_and_die("%s is mounted on %s; " "refusing to make a filesystem", - device_name, mp->mnt_dir); + G.device_name, mp->mnt_dir); - dev_fd = xopen(device_name, O_RDWR); - if (fstat(dev_fd, &statbuf) < 0) - bb_error_msg_and_die("cannot stat %s", device_name); + G.dev_fd = xopen(G.device_name, O_RDWR); + if (fstat(G.dev_fd, &statbuf) < 0) + bb_error_msg_and_die("cannot stat %s", G.device_name); if (!S_ISBLK(statbuf.st_mode)) opt &= ~1; // clear -c (check) @@ -673,16 +685,16 @@ int mkfs_minix_main(int argc, char **argv) else if (statbuf.st_rdev == 0x0300 || statbuf.st_rdev == 0x0340) /* what is this? */ bb_error_msg_and_die("will not try " - "to make filesystem on '%s'", device_name); + "to make filesystem on '%s'", G.device_name); #endif - tmp = root_block; + tmp = G.root_block; *(short *) tmp = 1; strcpy(tmp + 2, "."); - tmp += dirsize; + tmp += G.dirsize; *(short *) tmp = 1; strcpy(tmp + 2, ".."); - tmp += dirsize; + tmp += G.dirsize; *(short *) tmp = 2; strcpy(tmp + 2, ".badblocks"); |