From f5507d89293f00458f88624ffa98434d58b91e0f Mon Sep 17 00:00:00 2001 From: oharboe Date: Tue, 26 Aug 2008 11:29:59 +0000 Subject: [PATCH] do not check checksums in noack case git-svn-id: svn://svn.berlios.de/openocd/trunk@969 b42882b7-edfa-0310-969c-e2dbd0fdcd60 --- src/server/gdb_server.c | 228 ++++++++++++++++++++++------------------ 1 file changed, 124 insertions(+), 104 deletions(-) diff --git a/src/server/gdb_server.c b/src/server/gdb_server.c index 8fb3b64f..95fa8406 100644 --- a/src/server/gdb_server.c +++ b/src/server/gdb_server.c @@ -395,13 +395,119 @@ int gdb_put_packet(connection_t *connection, char *buffer, int len) return retval; } -int gdb_get_packet_inner(connection_t *connection, char *buffer, int *len) +static __inline__ int fetch_packet(connection_t *connection, int *checksum_ok, int noack, int *len, char *buffer) { + unsigned char my_checksum = 0; + char checksum[3]; int character; + int retval; + + gdb_connection_t *gdb_con = connection->priv; + my_checksum = 0; int count = 0; + count = 0; + for (;;) + { + /* The common case is that we have an entire packet with no escape chars. + * We need to leave at least 2 bytes in the buffer to have + * gdb_get_char() update various bits and bobs correctly. + */ + if ((gdb_con->buf_cnt > 2) && ((gdb_con->buf_cnt+count) < *len)) + { + /* The compiler will struggle a bit with constant propagation and + * aliasing, so we help it by showing that these values do not + * change inside the loop + */ + int i; + char *buf = gdb_con->buf_p; + int run = gdb_con->buf_cnt - 2; + i = 0; + int done = 0; + while (i < run) + { + character = *buf++; + i++; + if (character == '#') + { + /* Danger! character can be '#' when esc is + * used so we need an explicit boolean for done here. + */ + done = 1; + break; + } + + if (character == '}') + { + /* data transmitted in binary mode (X packet) + * uses 0x7d as escape character */ + my_checksum += character & 0xff; + character = *buf++; + i++; + my_checksum += character & 0xff; + buffer[count++] = (character ^ 0x20) & 0xff; + } + else + { + my_checksum += character & 0xff; + buffer[count++] = character & 0xff; + } + } + gdb_con->buf_p += i; + gdb_con->buf_cnt -= i; + if (done) + break; + } + if (count > *len) + { + LOG_ERROR("packet buffer too small"); + return ERROR_GDB_BUFFER_TOO_SMALL; + } + + if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) + return retval; + + if (character == '#') + break; + + if (character == '}') + { + /* data transmitted in binary mode (X packet) + * uses 0x7d as escape character */ + my_checksum += character & 0xff; + if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) + return retval; + my_checksum += character & 0xff; + buffer[count++] = (character ^ 0x20) & 0xff; + } + else + { + my_checksum += character & 0xff; + buffer[count++] = character & 0xff; + } + } + + *len = count; + + if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) + return retval; + checksum[0] = character; + if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) + return retval; + checksum[1] = character; + checksum[2] = 0; + + if (!noack) + { + *checksum_ok=(my_checksum == strtoul(checksum, NULL, 16)); + } + + return ERROR_OK; +} + +int gdb_get_packet_inner(connection_t *connection, char *buffer, int *len) +{ + int character; int retval; - char checksum[3]; - unsigned char my_checksum = 0; gdb_connection_t *gdb_con = connection->priv; while (1) @@ -437,116 +543,30 @@ int gdb_get_packet_inner(connection_t *connection, char *buffer, int *len) } } while (character != '$'); - my_checksum = 0; - count = 0; - gdb_connection_t *gdb_con = connection->priv; - for (;;) - { - /* The common case is that we have an entire packet with no escape chars. - * We need to leave at least 2 bytes in the buffer to have - * gdb_get_char() update various bits and bobs correctly. - */ - if ((gdb_con->buf_cnt > 2) && ((gdb_con->buf_cnt+count) < *len)) - { - /* The compiler will struggle a bit with constant propagation and - * aliasing, so we help it by showing that these values do not - * change inside the loop - */ - int i; - char *buf = gdb_con->buf_p; - int run = gdb_con->buf_cnt - 2; - i = 0; - int done = 0; - while (i < run) - { - character = *buf++; - i++; - if (character == '#') - { - /* Danger! character can be '#' when esc is - * used so we need an explicit boolean for done here. - */ - done = 1; - break; - } - if (character == '}') - { - /* data transmitted in binary mode (X packet) - * uses 0x7d as escape character */ - my_checksum += character & 0xff; - character = *buf++; - i++; - my_checksum += character & 0xff; - buffer[count++] = (character ^ 0x20) & 0xff; - } - else - { - my_checksum += character & 0xff; - buffer[count++] = character & 0xff; - } - } - gdb_con->buf_p += i; - gdb_con->buf_cnt -= i; - if (done) - break; - } - if (count > *len) - { - LOG_ERROR("packet buffer too small"); - return ERROR_GDB_BUFFER_TOO_SMALL; - } - - if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) + int checksum_ok; + /* explicit code expansion here to get faster inlined code in -O3 by not + * calculating checksum + */ + if (gdb_con->noack_mode) + { + if ((retval=fetch_packet(connection, &checksum_ok, 1, len, buffer))!=ERROR_OK) return retval; - - if (character == '#') - break; - - if (character == '}') - { - /* data transmitted in binary mode (X packet) - * uses 0x7d as escape character */ - my_checksum += character & 0xff; - if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) - return retval; - my_checksum += character & 0xff; - buffer[count++] = (character ^ 0x20) & 0xff; - } - else - { - my_checksum += character & 0xff; - buffer[count++] = character & 0xff; - } - } - - *len = count; - - if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) - return retval; - checksum[0] = character; - if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) - return retval; - checksum[1] = character; - checksum[2] = 0; - - if (my_checksum == strtoul(checksum, NULL, 16)) + } else { - if (gdb_con->noack_mode) - break; - gdb_write(connection, "+", 1); - break; + if ((retval=fetch_packet(connection, &checksum_ok, 0, len, buffer))!=ERROR_OK) + return retval; } - if (!gdb_con->noack_mode) + if (gdb_con->noack_mode) { - LOG_WARNING("checksum error, requesting retransmission"); - gdb_write(connection, "-", 1); + /* checksum is not checked in noack mode */ + break; } - else + if (checksum_ok) { - LOG_WARNING("checksum error, no-ack-mode"); + gdb_write(connection, "+", 1); break; } } -- 2.39.5