From 2356f89f27bd8429dbf7aa6a221415189035fc5b Mon Sep 17 00:00:00 2001 From: Leah Rowe Date: Thu, 6 Apr 2023 20:48:28 +0100 Subject: util/nvmutil: less annoying comments added a few that were more useful deleted a few obnoxious ones --- util/nvmutil/nvmutil.c | 53 +++++++++++++++----------------------------------- 1 file changed, 16 insertions(+), 37 deletions(-) (limited to 'util') diff --git a/util/nvmutil/nvmutil.c b/util/nvmutil/nvmutil.c index 508f76ee..4303337e 100644 --- a/util/nvmutil/nvmutil.c +++ b/util/nvmutil/nvmutil.c @@ -91,13 +91,13 @@ main(int argc, char *argv[]) gbe[1] = (gbe[0] = (size_t) buf) + SIZE_4KB; test = 1; - big_endian = ((uint8_t *) &test)[0] ^ 1; /* check host endianness */ + big_endian = ((uint8_t *) &test)[0] ^ 1; if (argc == 3) { if (strcmp(COMMAND, "dump") == 0) { #ifdef HAVE_PLEDGE - if (pledge("stdio rpath", NULL) == -1) - err(errno, "pledge"); /* not very puffy */ + if (pledge("stdio rpath", NULL) == -1) /* openbsd */ + err(errno, "pledge"); #endif flags = O_RDONLY; cmd = &cmd_dump; @@ -126,19 +126,18 @@ main(int argc, char *argv[]) nr = SIZE_4KB; /* copy/swap commands need everything to be read */ if ((cmd != &cmd_copy) && (cmd != &cmd_swap)) - nr = 128; /* read only the nvm part */ + nr = 128; /* speedhack: read only the nvm part */ if ((cmd == &cmd_copy) || (cmd == &cmd_setchecksum) || (cmd == &cmd_brick)) - skipread[part ^ 1] = 1; /* skip reading the unused part */ + skipread[part ^ 1] = 1; /* speedhack: don't read unused part */ readGbeFile(&fd, FILENAME, flags, nr); - /* perform operation specified by the user */ if (strMac != NULL) - cmd_setmac(strMac); + cmd_setmac(strMac); /* nvm gbe.bin setmac */ else if (cmd != NULL) - (*cmd)(); + (*cmd)(); /* all other commands except setmac */ if (gbeFileModified) writeGbeFile(&fd, FILENAME); @@ -151,7 +150,6 @@ nvmutil_exit: return errno; } -/* load the gbe file into memory */ void readGbeFile(int *fd, const char *path, int flags, size_t nr) { @@ -181,7 +179,6 @@ readGbeFile(int *fd, const char *path, int flags, size_t nr) } } -/* set mac address on valid nvm parts, per user input */ void cmd_setmac(const char *strMac) { @@ -193,20 +190,18 @@ cmd_setmac(const char *strMac) if (!validChecksum(partnum)) continue; for (int w = 0; w < 3; w++) - setWord(w, partnum, mac[w]); /* do not use memcpy! */ + setWord(w, partnum, mac[w]); byteswap(6, partnum); /* mac words are stored big-endian */ part = partnum; cmd_setchecksum(); } } -/* read mac address from user input */ int parseMacAddress(const char *strMac, uint16_t *mac) { uint8_t h; uint64_t total = 0; - if (strnlen(strMac, 20) != 17) return -1; @@ -226,10 +221,8 @@ parseMacAddress(const char *strMac, uint16_t *mac) << ((8 * ((byte % 2) ^ 1)) + (4 * (nib ^ 1))); } } - - /* Disallow multicast and all-zero MAC addresses */ return ((total == 0) || (mac[0] & 0x100)) - ? -1 : 0; + ? -1 : 0; /* disallow multicast/zero mac addresses */ } uint8_t @@ -247,7 +240,6 @@ hextonum(char ch) return 16; } -/* generate a random number from 0 to 15, the unix way */ uint8_t rhex(void) { @@ -265,7 +257,6 @@ rhex(void) return rval; } -/* show mac address and hexdump of each nvm part */ void cmd_dump(void) { @@ -281,7 +272,6 @@ cmd_dump(void) errno = 0; } -/* show formatted mac address contained within the nvm part */ void showmac(int partnum) { @@ -296,7 +286,6 @@ showmac(int partnum) } } -/* output a hexdump of both nvm parts, bytes reversed to big-endian order */ void hexdump(int partnum) { @@ -311,7 +300,6 @@ hexdump(int partnum) } } -/* set a valid checksum on a given part */ void cmd_setchecksum(void) { @@ -321,7 +309,6 @@ cmd_setchecksum(void) setWord(0x3F, part, 0xBABA - val16); } -/* set invalid checksum, intentionally */ void cmd_brick(void) { @@ -329,12 +316,11 @@ cmd_brick(void) setWord(0x3F, part, (word(0x3F, part)) ^ 0xFF); } -/* swap the words of each part with each other */ void cmd_swap(void) { if (validChecksum(1) || validChecksum(0)) { - gbe[0] ^= gbe[1]; /* speed hack: xorswap pointers, not words */ + gbe[0] ^= gbe[1]; /* speedhack: xorswap pointers, not words */ gbe[1] ^= gbe[0]; gbe[0] ^= gbe[1]; gbeFileModified = 1; /* not using setWord, so must set these */ @@ -344,12 +330,11 @@ cmd_swap(void) } } -/* overwrite one part with the other */ void cmd_copy(void) { if (validChecksum(part)) { - gbe[part ^ 1] = gbe[part]; /* pointer-based speed hack */ + gbe[part ^ 1] = gbe[part]; /* speedhack: copy ptr, not words */ gbeFileModified = 1; /* not using setWord, so must set these */ nvmPartModified[part ^ 1] = 1; } @@ -369,14 +354,12 @@ validChecksum(int partnum) return 0; } -/* fetch a word from gbe buffer */ uint16_t word(int pos16, int partnum) { return buf16[pos16 + (partnum << 11)]; } -/* write a word to gbe buffer, and record that a write has occured */ void setWord(int pos16, int partnum, uint16_t val16) { @@ -388,7 +371,6 @@ setWord(int pos16, int partnum, uint16_t val16) nvmPartModified[partnum] = 1; } -/* big-endian host compatibility: called post-read and again pre-write */ void byteswap(int n, int partnum) { @@ -396,28 +378,25 @@ byteswap(int n, int partnum) uint8_t *nbuf = (uint8_t *) gbe[partnum]; for (int w = 0; w < wcount; w++) { b1 = b2 = w << 1; - - /* xor-based swap method */ - nbuf[b1] ^= nbuf[++b2]; + nbuf[b1] ^= nbuf[++b2]; /* xor swap */ nbuf[b2] ^= nbuf[b1]; nbuf[b1] ^= nbuf[b2]; } } -/* called after all operations are done, if gbe was modified */ void writeGbeFile(int *fd, const char *filename) { int p, nw; errno = 0; if ((gbe[0] != gbe[1]) && (gbe[0] < gbe[1])) - nw = 128; /* write only the nvm part */ + nw = 128; /* speedhack: write only the nvm part */ else nw = SIZE_4KB; /* copy/swap, so only write everything */ for (p = 0; p < 2; p++) { - if (gbe[0] > gbe[1]) /* write sequentially on-disk */ - p ^= 1; + if (gbe[0] > gbe[1]) + p ^= 1; /* speedhack: write sequentially on-disk */ if (!nvmPartModified[p]) goto next_part; if (big_endian) @@ -426,7 +405,7 @@ writeGbeFile(int *fd, const char *filename) err(errno, "%s", filename); next_part: if (gbe[0] > gbe[1]) - p ^= 1; + p ^= 1; /* speedhack: write sequentially on-disk */ } if (close((*fd))) err(errno, "%s", filename); -- cgit v1.2.1