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Diffstat (limited to 'breakpoint.h')
| -rw-r--r-- | breakpoint.h | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/breakpoint.h b/breakpoint.h new file mode 100644 index 0000000..7cd914e --- /dev/null +++ b/breakpoint.h @@ -0,0 +1,138 @@ +/* + * This file is part of ltrace. + * Copyright (C) 2012 Petr Machata, Red Hat Inc. + * Copyright (C) 2009 Juan Cespedes + * + * 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 2 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, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + */ + +#ifndef BREAKPOINT_H +#define BREAKPOINT_H + +/* XXX This is currently a very weak abstraction. We would like to + * much expand this to allow things like breakpoints on SDT probes and + * such. + * + * In particular, we would like to add a tracepoint abstraction. + * Tracepoint is a traceable feature--e.g. an exact address, a DWARF + * symbol, an ELF symbol, a PLT entry, or an SDT probe. Tracepoints + * are named and the user can configure which of them he wants to + * enable. Realized tracepoints enable breakpoints, which are a + * low-level realization of high-level tracepoint. + * + * Service breakpoints like the handling of dlopen would be a + * low-level breakpoint, likely without tracepoint attached. + * + * So that's for sometimes. + */ + +#include "sysdep.h" +#include "library.h" + +struct Process; +struct breakpoint; + +struct bp_callbacks { + void (*on_hit)(struct breakpoint *bp, struct Process *proc); + void (*on_continue)(struct breakpoint *bp, struct Process *proc); + void (*on_retract)(struct breakpoint *bp, struct Process *proc); +}; + +struct breakpoint { + struct bp_callbacks *cbs; + struct library_symbol *libsym; + void *addr; + unsigned char orig_value[BREAKPOINT_LENGTH]; + int enabled; + struct arch_breakpoint_data arch; +}; + +/* Call on-hit handler of BP, if any is set. */ +void breakpoint_on_hit(struct breakpoint *bp, struct Process *proc); + +/* Call on-continue handler of BP. If none is set, call + * continue_after_breakpoint. */ +void breakpoint_on_continue(struct breakpoint *bp, struct Process *proc); + +/* Call on-retract handler of BP, if any is set. This should be + * called before the breakpoints are destroyed. The reason for a + * separate interface is that breakpoint_destroy has to be callable + * without PROC. ON_DISABLE might be useful as well, but that would + * be called every time we disable the breakpoint, which is too often + * (a breakpoint has to be disabled every time that we need to execute + * the instruction underneath it). */ +void breakpoint_on_retract(struct breakpoint *bp, struct Process *proc); + +/* Initialize a breakpoint structure. That doesn't actually realize + * the breakpoint. The breakpoint is initially assumed to be + * disabled. orig_value has to be set separately. CBS may be + * NULL. */ +int breakpoint_init(struct breakpoint *bp, struct Process *proc, + arch_addr_t addr, struct library_symbol *libsym); + +/* Make a clone of breakpoint BP into the area of memory pointed to by + * RETP. The original breakpoint was assigned to process OLD_PROC, + * the cloned breakpoint will be attached to process NEW_PROC. + * Returns 0 on success or a negative value on failure. */ +int breakpoint_clone(struct breakpoint *retp, struct Process *new_proc, + struct breakpoint *bp, struct Process *old_proc); + +/* Set callbacks. If CBS is non-NULL, then BP->cbs shall be NULL. */ +void breakpoint_set_callbacks(struct breakpoint *bp, struct bp_callbacks *cbs); + +/* Destroy a breakpoint structure. */ +void breakpoint_destroy(struct breakpoint *bp); + +/* Call enable_breakpoint the first time it's called. Returns 0 on + * success and a negative value on failure. */ +int breakpoint_turn_on(struct breakpoint *bp, struct Process *proc); + +/* Call disable_breakpoint when turned off the same number of times + * that it was turned on. Returns 0 on success and a negative value + * on failure. */ +int breakpoint_turn_off(struct breakpoint *bp, struct Process *proc); + +/* Utility function that does what typically needs to be done when a + * breakpoint is to be inserted. It checks whether there is another + * breakpoint in PROC->LEADER for given ADDR. If not, it allocates + * memory for a new breakpoint on the heap, initializes it, and calls + * PROC_ADD_BREAKPOINT to add the newly-created breakpoint. For newly + * added as well as preexisting breakpoints, it then calls + * BREAKPOINT_TURN_ON. If anything fails, it cleans up and returns + * NULL. Otherwise it returns the breakpoint for ADDR. */ +struct breakpoint *insert_breakpoint(struct Process *proc, void *addr, + struct library_symbol *libsym); + +/* Name of a symbol associated with BP. May be NULL. */ +const char *breakpoint_name(const struct breakpoint *bp); + +/* A library that this breakpoint comes from. May be NULL. */ +struct library *breakpoint_library(const struct breakpoint *bp); + +/* Again, this seems to be several interfaces rolled into one: + * - breakpoint_disable + * - proc_remove_breakpoint + * - breakpoint_destroy + * XXX */ +void delete_breakpoint(struct Process *proc, void *addr); + +/* XXX some of the following belongs to proc.h/proc.c. */ +struct breakpoint *address2bpstruct(struct Process *proc, void *addr); +void enable_all_breakpoints(struct Process *proc); +void disable_all_breakpoints(struct Process *proc); +int breakpoints_init(struct Process *proc); + +#endif /* BREAKPOINT_H */ |