From 351e23ad8e1b2b077bec77d6250d1c82fb04dd1f Mon Sep 17 00:00:00 2001 From: Wayne Davison Date: Fri, 20 Apr 2007 08:16:53 +0000 Subject: [PATCH] - Changed the {read,write}_longint() functions into separate {read,write}_varlong() and {read,write}_longint() functions: the former handles variable-length transmissions, and the latter is backward-compatible with older rsync versions. - Improved the {read,write}_var{int,long}() functions to be simpler and to use a different byte order. - The {read_write}_varlong() functions also allow the caller to specify the minimum number of bytes to send. This allows time values to be sent efficiently with a 4-byte minimum, while length values continue to be sent with a (more optimal for them) 3-byte minimum. --- io.c | 361 +++++++++++++++++++++++++---------------------------------- 1 file changed, 153 insertions(+), 208 deletions(-) diff --git a/io.c b/io.c index 25574409..b7ead41f 100644 --- a/io.c +++ b/io.c @@ -99,11 +99,11 @@ static int select_timeout = SELECT_TIMEOUT; static int active_filecnt = 0; static OFF_T active_bytecnt = 0; -static char int_byte_cnt[64] = { - 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* (00 - 3F)/4 */ - 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* (40 - 7F)/4 */ - 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, /* (80 - BF)/4 */ - 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 6, 7, /* (C0 - FF)/4 */ +static char int_byte_extra[64] = { + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* (00 - 3F)/4 */ + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* (40 - 7F)/4 */ + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* (80 - BF)/4 */ + 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 5, 6, /* (C0 - FF)/4 */ }; static void readfd(int fd, char *buffer, size_t N); @@ -296,7 +296,7 @@ static void read_msg_fd(void) } if (len) { readfd(fd, buf, len); - stats.total_read = read_longint(fd); + stats.total_read = read_varlong(fd, 3); } msgdone_cnt++; break; @@ -998,37 +998,6 @@ unsigned short read_shortint(int f) return (UVAL(b, 1) << 8) + UVAL(b, 0); } -int32 read_varint(int f) -{ - int32 num; - char b[5]; - int cnt; - readfd(f, b, 1); - cnt = int_byte_cnt[CVAL(b, 0) / 4]; - if (cnt > 1) - readfd(f, b + 1, cnt - 1); - switch (cnt) { - case 1: - num = NVAL1(b, 0); - break; - case 2: - num = NVAL2(b, 0x80); - break; - case 3: - num = NVAL3(b, 0xC0); - break; - case 4: - num = NVAL4(b, 0xE0); - break; - case 5: - num = NVAL4(b+1, 0); - break; - default: - exit_cleanup(RERR_PROTOCOL); /* impossible... */ - } - return num; -} - int32 read_int(int f) { char b[4]; @@ -1043,66 +1012,96 @@ int32 read_int(int f) return num; } -int64 read_longint(int f) +int32 read_varint(int f) { - int64 num; - char b[9]; - - if (protocol_version < 30) { - num = read_int(f); + union { + char b[5]; + int32 x; + } u; + uchar ch; + int extra; + + u.x = 0; + readfd(f, (char*)&ch, 1); + extra = int_byte_extra[ch / 4]; + if (extra) { + uchar bit = ((uchar)1<<(8-extra)); + if (extra >= (int)sizeof u.b) { + rprintf(FERROR, "Overflow in read_varint()\n"); + exit_cleanup(RERR_STREAMIO); + } + readfd(f, u.b, extra); + u.b[extra] = ch & (bit-1); + } else + u.b[0] = ch; +#if CAREFUL_ALIGNMENT + u.x = IVAL(u.b,0); +#endif +#if SIZEOF_INT32 > 4 + if (u.x & (int32)0x80000000) + u.x |= ~(int32)0xffffffff; +#endif + return u.x; +} - if ((int32)num != (int32)0xffffffff) - return num; +int64 read_varlong(int f, uchar min_bytes) +{ + union { + char b[9]; + int64 x; + } u; + char b2[8]; + int extra; #if SIZEOF_INT64 < 8 - rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n"); - exit_cleanup(RERR_UNSUPPORTED); + memset(u.b, 0, 8); #else - readfd(f, b, 8); - num = IVAL(b,0) | (((int64)IVAL(b,4))<<32); + u.x = 0; #endif - } else { - int cnt; - readfd(f, b, 3); - cnt = int_byte_cnt[CVAL(b, 0) / 4] + 2; + readfd(f, b2, min_bytes); + memcpy(u.b, b2+1, min_bytes-1); + extra = int_byte_extra[CVAL(b2, 0) / 4]; + if (extra) { + uchar bit = ((uchar)1<<(8-extra)); + if (min_bytes + extra > (int)sizeof u.b) { + rprintf(FERROR, "Overflow in read_varlong()\n"); + exit_cleanup(RERR_STREAMIO); + } + readfd(f, u.b + min_bytes - 1, extra); + u.b[min_bytes + extra - 1] = CVAL(b2, 0) & (bit-1); #if SIZEOF_INT64 < 8 - if (cnt > 5 || (cnt == 5 && (CVAL(b,0)&0x3F || CVAL(b,1)&0x80))) { + if (min_bytes + extra > 5 || u.b[4] || CVAL(u.b,3) & 0x80) { rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n"); exit_cleanup(RERR_UNSUPPORTED); } #endif - if (cnt > 3) - readfd(f, b + 3, cnt - 3); - switch (cnt) { - case 3: - num = NVAL3(b, 0); - break; - case 4: - num = NVAL4(b, 0x80); - break; - case 5: - num = NVAL5(b, 0xC0); - break; + } else + u.b[min_bytes + extra - 1] = CVAL(b2, 0); +#if SIZEOF_INT64 < 8 + u.x = IVAL(u.b,0); +#elif CAREFUL_ALIGNMENT + u.x = IVAL(u.b,0) | (((int64)IVAL(u.b,4))<<32); +#endif + return u.x; +} + +int64 read_longint(int f) +{ #if SIZEOF_INT64 >= 8 - case 6: - num = NVAL6(b, 0xE0); - break; - case 7: - num = NVAL7(b, 0xF0); - break; - case 8: - num = NVAL8(b, 0xF8); - break; - case 9: - num = NVAL8(b+1, 0); - break; + char b[9]; #endif - default: - exit_cleanup(RERR_PROTOCOL); /* impossible... */ - } - } + int32 num = read_int(f); - return num; + if (num != (int32)0xffffffff) + return num; + +#if SIZEOF_INT64 < 8 + rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n"); + exit_cleanup(RERR_UNSUPPORTED); +#else + readfd(f, b, 8); + return IVAL(b,0) | (((int64)IVAL(b,4))<<32); +#endif } void read_buf(int f, char *buf, size_t len) @@ -1404,42 +1403,65 @@ void write_shortint(int f, unsigned short x) writefd(f, b, 2); } +void write_int(int f, int32 x) +{ + char b[4]; + SIVAL(b, 0, x); + writefd(f, b, 4); +} + void write_varint(int f, int32 x) { char b[5]; - if ((uint32)x < ((uint32)1<<(1*8-1))) { - b[0] = (char)x; - writefd(f, b, 1); - } else if ((uint32)x < ((uint32)1<<(2*8-2))) { - b[0] = (char)(x >> 8) | 0x80; - b[1] = (char)x; - writefd(f, b, 2); - } else if ((uint32)x < ((uint32)1<<(3*8-3))) { - b[0] = (char)(x >> 16) | 0xC0; - b[1] = (char)(x >> 8); - b[2] = (char)x; - writefd(f, b, 3); - } else if ((uint32)x < ((uint32)1<<(4*8-4))) { - b[0] = (char)(x >> 24) | 0xE0; - b[1] = (char)(x >> 16); - b[2] = (char)(x >> 8); - b[3] = (char)x; - writefd(f, b, 4); - } else { - b[0] = 0xF0; - b[1] = (char)(x >> 24); - b[2] = (char)(x >> 16); - b[3] = (char)(x >> 8); - b[4] = (char)x; - writefd(f, b, 5); - } + uchar bit; + int cnt = 4; + + SIVAL(b, 1, x); + + while (cnt > 1 && b[cnt] == 0) + cnt--; + bit = ((uchar)1<<(7-cnt+1)); + if (CVAL(b, cnt) >= bit) { + cnt++; + *b = ~(bit-1); + } else if (cnt > 1) + *b = b[cnt] | ~(bit*2-1); + else + *b = b[cnt]; + + writefd(f, b, cnt); } -void write_int(int f, int32 x) +void write_varlong(int f, int64 x, uchar min_bytes) { - char b[4]; - SIVAL(b, 0, x); - writefd(f, b, 4); + char b[9]; + uchar bit; + int cnt = 8; + + SIVAL(b, 1, x); +#if SIZEOF_INT64 >= 8 + SIVAL(b, 5, x >> 32); +#else + if (x <= 0x7FFFFFFF && x >= 0) + memset(b + 5, 0, 4); + else { + rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n"); + exit_cleanup(RERR_UNSUPPORTED); + } +#endif + + while (cnt > min_bytes && b[cnt] == 0) + cnt--; + bit = ((uchar)1<<(7-cnt+min_bytes)); + if (CVAL(b, cnt) >= bit) { + cnt++; + *b = ~(bit-1); + } else if (cnt > min_bytes) + *b = b[cnt] | ~(bit*2-1); + else + *b = b[cnt]; + + writefd(f, b, cnt); } /* @@ -1448,100 +1470,21 @@ void write_int(int f, int32 x) */ void write_longint(int f, int64 x) { - char b[12]; + char b[12], * const s = b+4; -#if SIZEOF_INT64 < 8 - if (x < 0 || x > 0x7FFFFFFF) { - rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n"); - exit_cleanup(RERR_UNSUPPORTED); - } -#endif - - if (protocol_version < 30) { - char * const s = b+4; - SIVAL(s, 0, x); -#if SIZEOF_INT64 < 8 + SIVAL(s, 0, x); + if (x <= 0x7FFFFFFF && x >= 0) { writefd(f, s, 4); -#else - if (x <= 0x7FFFFFFF && x >= 0) { - writefd(f, s, 4); - return; - } + return; + } - memset(b, 0xFF, 4); - SIVAL(s, 4, x >> 32); - writefd(f, b, 12); - } else if (x < 0) { - goto all_bits; -#endif - } else if (x < ((int32)1<<(3*8-1))) { - b[0] = (char)(x >> 16); - b[1] = (char)(x >> 8); - b[2] = (char)x; - writefd(f, b, 3); - } else if (x < ((int64)1<<(4*8-2))) { - b[0] = (char)((x >> 24) | 0x80); - b[1] = (char)(x >> 16); - b[2] = (char)(x >> 8); - b[3] = (char)x; - writefd(f, b, 4); #if SIZEOF_INT64 < 8 - } else { - b[0] = 0xC0; - b[1] = (char)(x >> 24); - b[2] = (char)(x >> 16); - b[3] = (char)(x >> 8); - b[4] = (char)x; - writefd(f, b, 5); - } + rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n"); + exit_cleanup(RERR_UNSUPPORTED); #else - } else if (x < ((int64)1<<(5*8-3))) { - b[0] = (char)((x >> 32) | 0xC0); - b[1] = (char)(x >> 24); - b[2] = (char)(x >> 16); - b[3] = (char)(x >> 8); - b[4] = (char)x; - writefd(f, b, 5); - } else if (x < ((int64)1<<(6*8-4))) { - b[0] = (char)((x >> 40) | 0xE0); - b[1] = (char)(x >> 32); - b[2] = (char)(x >> 24); - b[3] = (char)(x >> 16); - b[4] = (char)(x >> 8); - b[5] = (char)x; - writefd(f, b, 6); - } else if (x < ((int64)1<<(7*8-5))) { - b[0] = (char)((x >> 48) | 0xF0); - b[1] = (char)(x >> 40); - b[2] = (char)(x >> 32); - b[3] = (char)(x >> 24); - b[4] = (char)(x >> 16); - b[5] = (char)(x >> 8); - b[6] = (char)x; - writefd(f, b, 7); - } else if (x < ((int64)1<<(8*8-6))) { - b[0] = (char)((x >> 56) | 0xF8); - b[1] = (char)(x >> 48); - b[2] = (char)(x >> 40); - b[3] = (char)(x >> 32); - b[4] = (char)(x >> 24); - b[5] = (char)(x >> 16); - b[6] = (char)(x >> 8); - b[7] = (char)x; - writefd(f, b, 8); - } else { - all_bits: - b[0] = (char)0xFC; - b[1] = (char)(x >> 56); - b[2] = (char)(x >> 48); - b[3] = (char)(x >> 40); - b[4] = (char)(x >> 32); - b[5] = (char)(x >> 24); - b[6] = (char)(x >> 16); - b[7] = (char)(x >> 8); - b[8] = (char)x; - writefd(f, b, 9); - } + memset(b, 0xFF, 4); + SIVAL(s, 4, x >> 32); + writefd(f, b, 12); #endif } @@ -1617,9 +1560,9 @@ void write_ndx(int f, int32 ndx) else if (diff < 0 || diff > 0x7FFF) { b[cnt++] = (char)0xFE; b[cnt++] = (char)((ndx >> 24) | 0x80); - b[cnt++] = (char)(ndx >> 16); - b[cnt++] = (char)(ndx >> 8); b[cnt++] = (char)ndx; + b[cnt++] = (char)(ndx >> 8); + b[cnt++] = (char)(ndx >> 16); } else { b[cnt++] = (char)0xFE; b[cnt++] = (char)(diff >> 8); @@ -1649,12 +1592,14 @@ int32 read_ndx(int f) if (CVAL(b, 0) == 0xFE) { readfd(f, b, 2); if (CVAL(b, 0) & 0x80) { - readfd(f, b+2, 2); - num = NVAL4(b, 0x80); + b[3] = CVAL(b, 0) & ~0x80; + b[0] = b[1]; + readfd(f, b+1, 2); + num = IVAL(b, 0); } else - num = NVAL2(b, 0) + *prev_ptr; + num = (UVAL(b,0)<<8) + UVAL(b,1) + *prev_ptr; } else - num = CVAL(b, 0) + *prev_ptr; + num = UVAL(b, 0) + *prev_ptr; *prev_ptr = num; if (prev_ptr == &prev_negative) num = -num; -- 2.34.1