From 30ba68cb7eb8f662d7728f3b8d26a3933859ff5a Mon Sep 17 00:00:00 2001 From: Michael Snyder Date: Tue, 23 Mar 2010 22:43:50 +0000 Subject: [PATCH] 2010-03-23 Michael Snyder * server.c (crc32): New function. (handle_query): Add handling for 'qCRC:' request. --- gdb/gdbserver/ChangeLog | 5 +++ gdb/gdbserver/server.c | 68 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 73 insertions(+) diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index 552c83d5ee9..cab5a73a702 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,8 @@ +2010-03-23 Michael Snyder + + * server.c (crc32): New function. + (handle_query): Add handling for 'qCRC:' request. + 2010-03-23 Pedro Alves * linux-x86-low.c (x86_linux_prepare_to_resume): Clear DR6 if the diff --git a/gdb/gdbserver/server.c b/gdb/gdbserver/server.c index a03f8774cd6..05a41bfd9d1 100644 --- a/gdb/gdbserver/server.c +++ b/gdb/gdbserver/server.c @@ -788,6 +788,47 @@ handle_threads_qxfer (const char *annex, } +/* Table used by the crc32 function to calcuate the checksum. */ + +static unsigned int crc32_table[256] = +{0, 0}; + +/* Compute 32 bit CRC from inferior memory. + + On success, return 32 bit CRC. + On failure, return (unsigned long long) -1. */ + +static unsigned long long +crc32 (CORE_ADDR base, int len, unsigned int crc) +{ + if (!crc32_table[1]) + { + /* Initialize the CRC table and the decoding table. */ + int i, j; + unsigned int c; + + for (i = 0; i < 256; i++) + { + for (c = i << 24, j = 8; j > 0; --j) + c = c & 0x80000000 ? (c << 1) ^ 0x04c11db7 : (c << 1); + crc32_table[i] = c; + } + } + + while (len--) + { + unsigned char byte = 0; + + /* Return failure if memory read fails. */ + if (read_inferior_memory (base, &byte, 1) != 0) + return (unsigned long long) -1; + + crc = (crc << 8) ^ crc32_table[((crc >> 24) ^ byte) & 255]; + base++; + } + return (unsigned long long) crc; +} + /* Handle all of the extended 'q' packets. */ void handle_query (char *own_buf, int packet_len, int *new_packet_len_p) @@ -1421,6 +1462,33 @@ handle_query (char *own_buf, int packet_len, int *new_packet_len_p) return; } + if (strncmp ("qCRC:", own_buf, 5) == 0) + { + /* CRC check (compare-section). */ + char *comma; + CORE_ADDR base; + int len; + unsigned long long crc; + + require_running (own_buf); + base == strtoul (own_buf + 5, &comma, 16); + if (*comma++ != ',') + { + write_enn (own_buf); + return; + } + len = strtoul (comma, NULL, 16); + crc = crc32 (base, len, 0xffffffff); + /* Check for memory failure. */ + if (crc == (unsigned long long) -1) + { + write_enn (own_buf); + return; + } + sprintf (own_buf, "C%lx", (unsigned long) crc); + return; + } + /* Otherwise we didn't know what packet it was. Say we didn't understand it. */ own_buf[0] = 0; -- 2.30.2