From 55b10d89a413169b2d001df701b7c08e06f955aa Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Wed, 7 Oct 2020 12:07:55 -0600 Subject: [PATCH] Use simple_search_memory in gdbserver This replaces gdbserver's memory-searching function with simple_search_memory. gdbserver/ChangeLog 2020-10-07 Tom Tromey * server.cc (handle_search_memory_1): Remove. (handle_search_memory): Use simple_search_memory. --- gdbserver/ChangeLog | 5 ++ gdbserver/server.cc | 113 +++----------------------------------------- 2 files changed, 11 insertions(+), 107 deletions(-) diff --git a/gdbserver/ChangeLog b/gdbserver/ChangeLog index 94f1a75b94d..a341693776c 100644 --- a/gdbserver/ChangeLog +++ b/gdbserver/ChangeLog @@ -1,3 +1,8 @@ +2020-10-07 Tom Tromey + + * server.cc (handle_search_memory_1): Remove. + (handle_search_memory): Use simple_search_memory. + 2020-10-07 Simon Marchi * Makefile.in (COMPILE): Add CXXFLAGS. diff --git a/gdbserver/server.cc b/gdbserver/server.cc index e6314e56506..86c9a6f22b8 100644 --- a/gdbserver/server.cc +++ b/gdbserver/server.cc @@ -49,6 +49,7 @@ #include "gdbsupport/scope-exit.h" #include "gdbsupport/gdb_select.h" #include "gdbsupport/scoped_restore.h" +#include "gdbsupport/search.h" #define require_running_or_return(BUF) \ if (!target_running ()) \ @@ -1040,89 +1041,6 @@ gdb_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len) } } -/* Subroutine of handle_search_memory to simplify it. */ - -static int -handle_search_memory_1 (CORE_ADDR start_addr, CORE_ADDR search_space_len, - gdb_byte *pattern, unsigned pattern_len, - gdb_byte *search_buf, - unsigned chunk_size, unsigned search_buf_size, - CORE_ADDR *found_addrp) -{ - /* Prime the search buffer. */ - - if (gdb_read_memory (start_addr, search_buf, search_buf_size) - != search_buf_size) - { - warning ("Unable to access %ld bytes of target " - "memory at 0x%lx, halting search.", - (long) search_buf_size, (long) start_addr); - return -1; - } - - /* Perform the search. - - The loop is kept simple by allocating [N + pattern-length - 1] bytes. - When we've scanned N bytes we copy the trailing bytes to the start and - read in another N bytes. */ - - while (search_space_len >= pattern_len) - { - gdb_byte *found_ptr; - unsigned nr_search_bytes = (search_space_len < search_buf_size - ? search_space_len - : search_buf_size); - - found_ptr = (gdb_byte *) memmem (search_buf, nr_search_bytes, pattern, - pattern_len); - - if (found_ptr != NULL) - { - CORE_ADDR found_addr = start_addr + (found_ptr - search_buf); - *found_addrp = found_addr; - return 1; - } - - /* Not found in this chunk, skip to next chunk. */ - - /* Don't let search_space_len wrap here, it's unsigned. */ - if (search_space_len >= chunk_size) - search_space_len -= chunk_size; - else - search_space_len = 0; - - if (search_space_len >= pattern_len) - { - unsigned keep_len = search_buf_size - chunk_size; - CORE_ADDR read_addr = start_addr + chunk_size + keep_len; - int nr_to_read; - - /* Copy the trailing part of the previous iteration to the front - of the buffer for the next iteration. */ - memcpy (search_buf, search_buf + chunk_size, keep_len); - - nr_to_read = (search_space_len - keep_len < chunk_size - ? search_space_len - keep_len - : chunk_size); - - if (gdb_read_memory (read_addr, search_buf + keep_len, - nr_to_read) != nr_to_read) - { - warning ("Unable to access %ld bytes of target memory " - "at 0x%lx, halting search.", - (long) nr_to_read, (long) read_addr); - return -1; - } - - start_addr += chunk_size; - } - } - - /* Not found. */ - - return 0; -} - /* Handle qSearch:memory packets. */ static void @@ -1132,12 +1050,6 @@ handle_search_memory (char *own_buf, int packet_len) CORE_ADDR search_space_len; gdb_byte *pattern; unsigned int pattern_len; - /* NOTE: also defined in find.c testcase. */ -#define SEARCH_CHUNK_SIZE 16000 - const unsigned chunk_size = SEARCH_CHUNK_SIZE; - /* Buffer to hold memory contents for searching. */ - gdb_byte *search_buf; - unsigned search_buf_size; int found; CORE_ADDR found_addr; int cmd_name_len = sizeof ("qSearch:memory:") - 1; @@ -1160,25 +1072,13 @@ handle_search_memory (char *own_buf, int packet_len) return; } - search_buf_size = chunk_size + pattern_len - 1; - - /* No point in trying to allocate a buffer larger than the search space. */ - if (search_space_len < search_buf_size) - search_buf_size = search_space_len; - - search_buf = (gdb_byte *) malloc (search_buf_size); - if (search_buf == NULL) + auto read_memory = [] (CORE_ADDR addr, gdb_byte *result, size_t len) { - free (pattern); - error ("Unable to allocate memory to perform the search"); - strcpy (own_buf, "E00"); - return; - } + return gdb_read_memory (addr, result, len) == len; + }; - found = handle_search_memory_1 (start_addr, search_space_len, - pattern, pattern_len, - search_buf, chunk_size, search_buf_size, - &found_addr); + found = simple_search_memory (read_memory, start_addr, search_space_len, + pattern, pattern_len, &found_addr); if (found > 0) sprintf (own_buf, "1,%lx", (long) found_addr); @@ -1187,7 +1087,6 @@ handle_search_memory (char *own_buf, int packet_len) else strcpy (own_buf, "E00"); - free (search_buf); free (pattern); } -- 2.30.2