diff options
| -rw-r--r-- | gdb/ChangeLog | 7 | ||||
| -rw-r--r-- | gdb/remote.c | 11 | ||||
| -rw-r--r-- | gdb/target.c | 110 | ||||
| -rw-r--r-- | gdb/target.h | 8 | ||||
| -rw-r--r-- | gdbsupport/ChangeLog | 7 | ||||
| -rw-r--r-- | gdbsupport/Makefile.am | 1 | ||||
| -rw-r--r-- | gdbsupport/Makefile.in | 4 | ||||
| -rw-r--r-- | gdbsupport/search.cc | 120 | ||||
| -rw-r--r-- | gdbsupport/search.h | 42 |
9 files changed, 197 insertions, 113 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 48ab2e0..0b92bfb 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,10 @@ +2020-10-07 Tom Tromey <tromey@adacore.com> + + * target.h (simple_search_memory): Don't declare. + * target.c (simple_search_memory): Move to gdbsupport. + (default_search_memory): Update. + * remote.c (remote_target::search_memory): Update. + 2020-10-07 Simon Marchi <simon.marchi@efficios.com> * Makefile.in (COMPILE): Add CXXFLAGS. diff --git a/gdb/remote.c b/gdb/remote.c index f951486..26ee28d 100644 --- a/gdb/remote.c +++ b/gdb/remote.c @@ -75,6 +75,7 @@ #include "gdbsupport/scoped_restore.h" #include "gdbsupport/environ.h" #include "gdbsupport/byte-vector.h" +#include "gdbsupport/search.h" #include <algorithm> #include <unordered_map> #include "async-event.h" @@ -11186,6 +11187,12 @@ remote_target::search_memory (CORE_ADDR start_addr, ULONGEST search_space_len, int found; ULONGEST found_addr; + auto read_memory = [=] (CORE_ADDR addr, gdb_byte *result, size_t len) + { + return (target_read (this, TARGET_OBJECT_MEMORY, NULL, result, addr, len) + == len); + }; + /* Don't go to the target if we don't have to. This is done before checking packet_config_support to avoid the possibility that a success for this edge case means the facility works in @@ -11205,7 +11212,7 @@ remote_target::search_memory (CORE_ADDR start_addr, ULONGEST search_space_len, { /* Target doesn't provided special support, fall back and use the standard support (copy memory and do the search here). */ - return simple_search_memory (this, start_addr, search_space_len, + return simple_search_memory (read_memory, start_addr, search_space_len, pattern, pattern_len, found_addrp); } @@ -11237,7 +11244,7 @@ remote_target::search_memory (CORE_ADDR start_addr, ULONGEST search_space_len, supported. If so, fall back to the simple way. */ if (packet_config_support (packet) == PACKET_DISABLE) { - return simple_search_memory (this, start_addr, search_space_len, + return simple_search_memory (read_memory, start_addr, search_space_len, pattern, pattern_len, found_addrp); } return -1; diff --git a/gdb/target.c b/gdb/target.c index dd78a84..6fd60a1 100644 --- a/gdb/target.c +++ b/gdb/target.c @@ -47,6 +47,7 @@ #include "event-top.h" #include <algorithm> #include "gdbsupport/byte-vector.h" +#include "gdbsupport/search.h" #include "terminal.h" #include <unordered_map> #include "target-connection.h" @@ -2147,106 +2148,6 @@ target_read_description (struct target_ops *target) return target->read_description (); } -/* This implements a basic search of memory, reading target memory and - performing the search here (as opposed to performing the search in on the - target side with, for example, gdbserver). */ - -int -simple_search_memory (struct target_ops *ops, - CORE_ADDR start_addr, ULONGEST search_space_len, - const gdb_byte *pattern, ULONGEST pattern_len, - CORE_ADDR *found_addrp) -{ - /* 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. */ - unsigned search_buf_size; - - 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; - - gdb::byte_vector search_buf (search_buf_size); - - /* Prime the search buffer. */ - - if (target_read (ops, TARGET_OBJECT_MEMORY, NULL, - search_buf.data (), start_addr, search_buf_size) - != search_buf_size) - { - warning (_("Unable to access %s bytes of target " - "memory at %s, halting search."), - pulongest (search_buf_size), hex_string (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 - = std::min (search_space_len, (ULONGEST) search_buf_size); - - found_ptr = (gdb_byte *) memmem (search_buf.data (), nr_search_bytes, - pattern, pattern_len); - - if (found_ptr != NULL) - { - CORE_ADDR found_addr = start_addr + (found_ptr - search_buf.data ()); - - *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. */ - gdb_assert (keep_len == pattern_len - 1); - memcpy (&search_buf[0], &search_buf[chunk_size], keep_len); - - nr_to_read = std::min (search_space_len - keep_len, - (ULONGEST) chunk_size); - - if (target_read (ops, TARGET_OBJECT_MEMORY, NULL, - &search_buf[keep_len], read_addr, - nr_to_read) != nr_to_read) - { - warning (_("Unable to access %s bytes of target " - "memory at %s, halting search."), - plongest (nr_to_read), - hex_string (read_addr)); - return -1; - } - - start_addr += chunk_size; - } - } - - /* Not found. */ - - return 0; -} /* Default implementation of memory-searching. */ @@ -2256,9 +2157,14 @@ default_search_memory (struct target_ops *self, const gdb_byte *pattern, ULONGEST pattern_len, CORE_ADDR *found_addrp) { + auto read_memory = [=] (CORE_ADDR addr, gdb_byte *result, size_t len) + { + return target_read (current_top_target (), TARGET_OBJECT_MEMORY, NULL, + result, addr, len) == len; + }; + /* Start over from the top of the target stack. */ - return simple_search_memory (current_top_target (), - start_addr, search_space_len, + return simple_search_memory (read_memory, start_addr, search_space_len, pattern, pattern_len, found_addrp); } diff --git a/gdb/target.h b/gdb/target.h index 695f1b2..8545533 100644 --- a/gdb/target.h +++ b/gdb/target.h @@ -2129,14 +2129,6 @@ extern const struct target_desc *target_read_description (struct target_ops *); #define target_get_ada_task_ptid(lwp, tid) \ (current_top_target ()->get_ada_task_ptid) (lwp,tid) -/* Utility implementation of searching memory. */ -extern int simple_search_memory (struct target_ops* ops, - CORE_ADDR start_addr, - ULONGEST search_space_len, - const gdb_byte *pattern, - ULONGEST pattern_len, - CORE_ADDR *found_addrp); - /* Main entry point for searching memory. */ extern int target_search_memory (CORE_ADDR start_addr, ULONGEST search_space_len, diff --git a/gdbsupport/ChangeLog b/gdbsupport/ChangeLog index 05462e6..adcc53a 100644 --- a/gdbsupport/ChangeLog +++ b/gdbsupport/ChangeLog @@ -1,3 +1,10 @@ +2020-10-07 Tom Tromey <tromey@adacore.com> + + * Makefile.in: Rebuild. + * Makefile.am (libgdbsupport_a_SOURCES): Add search.cc. + * search.h: New file. + * search.cc: New file. + 2020-10-02 Simon Marchi <simon.marchi@polymtl.ca> * event-loop.h (debug_event_loop): New variable declaration. diff --git a/gdbsupport/Makefile.am b/gdbsupport/Makefile.am index 9763c96..9f4ec93 100644 --- a/gdbsupport/Makefile.am +++ b/gdbsupport/Makefile.am @@ -65,6 +65,7 @@ libgdbsupport_a_SOURCES = \ run-time-clock.cc \ safe-strerror.cc \ scoped_mmap.cc \ + search.cc \ signals.cc \ signals-state-save-restore.cc \ tdesc.cc \ diff --git a/gdbsupport/Makefile.in b/gdbsupport/Makefile.in index 0223f6d..044ef15 100644 --- a/gdbsupport/Makefile.in +++ b/gdbsupport/Makefile.in @@ -156,7 +156,7 @@ am_libgdbsupport_a_OBJECTS = agent.$(OBJEXT) btrace-common.$(OBJEXT) \ netstuff.$(OBJEXT) new-op.$(OBJEXT) pathstuff.$(OBJEXT) \ print-utils.$(OBJEXT) ptid.$(OBJEXT) rsp-low.$(OBJEXT) \ run-time-clock.$(OBJEXT) safe-strerror.$(OBJEXT) \ - scoped_mmap.$(OBJEXT) signals.$(OBJEXT) \ + scoped_mmap.$(OBJEXT) search.$(OBJEXT) signals.$(OBJEXT) \ signals-state-save-restore.$(OBJEXT) tdesc.$(OBJEXT) \ thread-pool.$(OBJEXT) xml-utils.$(OBJEXT) $(am__objects_1) libgdbsupport_a_OBJECTS = $(am_libgdbsupport_a_OBJECTS) @@ -388,6 +388,7 @@ libgdbsupport_a_SOURCES = \ run-time-clock.cc \ safe-strerror.cc \ scoped_mmap.cc \ + search.cc \ signals.cc \ signals-state-save-restore.cc \ tdesc.cc \ @@ -492,6 +493,7 @@ distclean-compile: @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/run-time-clock.Po@am__quote@ @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/safe-strerror.Po@am__quote@ @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/scoped_mmap.Po@am__quote@ +@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/search.Po@am__quote@ @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/selftest.Po@am__quote@ @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/signals-state-save-restore.Po@am__quote@ @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/signals.Po@am__quote@ diff --git a/gdbsupport/search.cc b/gdbsupport/search.cc new file mode 100644 index 0000000..f10c570 --- /dev/null +++ b/gdbsupport/search.cc @@ -0,0 +1,120 @@ +/* Target memory searching + + Copyright (C) 2020 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "gdbsupport/common-defs.h" + +#include "gdbsupport/search.h" +#include "gdbsupport/byte-vector.h" + +/* This implements a basic search of memory, reading target memory and + performing the search here (as opposed to performing the search in on the + target side with, for example, gdbserver). */ + +int +simple_search_memory + (gdb::function_view<target_read_memory_ftype> read_memory, + CORE_ADDR start_addr, ULONGEST search_space_len, + const gdb_byte *pattern, ULONGEST pattern_len, + CORE_ADDR *found_addrp) +{ + const unsigned chunk_size = SEARCH_CHUNK_SIZE; + /* Buffer to hold memory contents for searching. */ + unsigned search_buf_size; + + 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; + + gdb::byte_vector search_buf (search_buf_size); + + /* Prime the search buffer. */ + + if (!read_memory (start_addr, search_buf.data (), search_buf_size)) + { + warning (_("Unable to access %s bytes of target " + "memory at %s, halting search."), + pulongest (search_buf_size), hex_string (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 + = std::min (search_space_len, (ULONGEST) search_buf_size); + + found_ptr = (gdb_byte *) memmem (search_buf.data (), nr_search_bytes, + pattern, pattern_len); + + if (found_ptr != NULL) + { + CORE_ADDR found_addr = start_addr + (found_ptr - search_buf.data ()); + + *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. */ + gdb_assert (keep_len == pattern_len - 1); + if (keep_len > 0) + memcpy (&search_buf[0], &search_buf[chunk_size], keep_len); + + nr_to_read = std::min (search_space_len - keep_len, + (ULONGEST) chunk_size); + + if (!read_memory (read_addr, &search_buf[keep_len], nr_to_read)) + { + warning (_("Unable to access %s bytes of target " + "memory at %s, halting search."), + plongest (nr_to_read), + hex_string (read_addr)); + return -1; + } + + start_addr += chunk_size; + } + } + + /* Not found. */ + + return 0; +} diff --git a/gdbsupport/search.h b/gdbsupport/search.h new file mode 100644 index 0000000..886d80f --- /dev/null +++ b/gdbsupport/search.h @@ -0,0 +1,42 @@ +/* Copyright (C) 2020 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#ifndef COMMON_SEARCH_H +#define COMMON_SEARCH_H + +#include "gdbsupport/function-view.h" + +/* This is needed by the unit test, so appears here. */ +#define SEARCH_CHUNK_SIZE 16000 + +/* The type of a callback function that can be used to read memory. + Note that target_read_memory is not used here, because gdbserver + wants to be able to examine trace data when searching, and + target_read_memory does not do this. */ + +typedef bool target_read_memory_ftype (CORE_ADDR, gdb_byte *, size_t); + +/* Utility implementation of searching memory. */ +extern int simple_search_memory + (gdb::function_view<target_read_memory_ftype> read_memory, + CORE_ADDR start_addr, + ULONGEST search_space_len, + const gdb_byte *pattern, + ULONGEST pattern_len, + CORE_ADDR *found_addrp); + +#endif /* COMMON_SEARCH_H */ |