From f929a5791d64e48f9abee0467d3a7b1ca4bc0bf0 Mon Sep 17 00:00:00 2001 From: Andrew Cagney Date: Thu, 30 Sep 2004 15:47:30 +0000 Subject: [PATCH] 2004-09-30 Andrew Cagney * inf-ptrace.c (inf_ptrace_xfer_partial): Replace call to inf_ptrace_xfer_memory with equivalent code. * inftarg.c (child_xfer_partial): When performing a write, pass writebuf to child_xfer_memory. --- gdb/ChangeLog | 5 +++ gdb/inf-ptrace.c | 98 ++++++++++++++++++++++++++++++++++++++++++++---- gdb/inftarg.c | 2 +- 3 files changed, 97 insertions(+), 8 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 3d6faccdc7a..4364731b00c 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,10 @@ 2004-09-30 Andrew Cagney + * inf-ptrace.c (inf_ptrace_xfer_partial): Replace call to + inf_ptrace_xfer_memory with equivalent code. + * inftarg.c (child_xfer_partial): When performing a write, pass + writebuf to child_xfer_memory. + * target.c (target_read_string): Use target_read_memory instead of target_xfer_memory. diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c index 14b3f0a4964..7c37a04df2c 100644 --- a/gdb/inf-ptrace.c +++ b/gdb/inf-ptrace.c @@ -619,13 +619,97 @@ inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object, switch (object) { case TARGET_OBJECT_MEMORY: - if (readbuf) - return inf_ptrace_xfer_memory (offset, readbuf, len, 0 /*write */ , - NULL, ops); - if (writebuf) - return inf_ptrace_xfer_memory (offset, readbuf, len, 1 /*write */ , - NULL, ops); - return -1; +#ifdef PT_IO + /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO + request that promises to be much more efficient in reading + and writing data in the traced process's address space. */ + { + struct ptrace_io_desc piod; + + /* NOTE: We assume that there are no distinct address spaces + for instruction and data. */ + piod.piod_op = writebuf ? PIOD_WRITE_D : PIOD_READ_D; + piod.piod_addr = writebuf ? (void *) writebuf : readbuf; + piod.piod_offs = (void *) (long) offset; + piod.piod_len = len; + + errno = 0; + if (ptrace (PT_IO, PIDGET (inferior_ptid), (caddr_t) &piod, 0) == 0) + /* Return the actual number of bytes read or written. */ + return piod.piod_len; + /* If the PT_IO request is somehow not supported, fallback on + using PT_WRITE_D/PT_READ_D. Otherwise we will return zero + to indicate failure. */ + if (errno != EINVAL) + return 0; + } +#endif + { + union + { + PTRACE_TYPE_RET word; + unsigned char byte[sizeof (PTRACE_TYPE_RET)]; + } buffer; + ULONGEST rounded_offset; + LONGEST partial_len; + + /* Round the start address down to the next long word boundary. */ + rounded_offset = offset & -(ULONGEST) sizeof (PTRACE_TYPE_RET); + + /* Truncate the length so that at max a single word will be + transfered. Remember, this function is required to perform + only a partial read so no more than one word should be + transfered). */ + if (rounded_offset + sizeof (PTRACE_TYPE_RET) < offset + len) + partial_len = sizeof (PTRACE_TYPE_RET) - (offset - rounded_offset); + else + partial_len = len; + + if (writebuf) + { + /* Fill start and end extra bytes of buffer with existing + memory data. */ + if (rounded_offset < offset + || (partial_len + (offset - rounded_offset) + < sizeof (PTRACE_TYPE_RET))) + /* Need part of initial word -- fetch it. */ + buffer.word = ptrace (PT_READ_I, PIDGET (inferior_ptid), + (PTRACE_TYPE_ARG3) (long) rounded_offset, + 0); + + /* Copy data to be written over corresponding part of + buffer. */ + memcpy (buffer.byte + (offset - rounded_offset), writebuf, partial_len); + + errno = 0; + ptrace (PT_WRITE_D, PIDGET (inferior_ptid), + (PTRACE_TYPE_ARG3) (long) rounded_offset, + (int) buffer.byte); + if (errno) + { + /* Using the appropriate one (I or D) is necessary for + Gould NP1, at least. */ + errno = 0; + ptrace (PT_WRITE_I, PIDGET (inferior_ptid), + (PTRACE_TYPE_ARG3) (long) rounded_offset, + (int) buffer.byte); + if (errno) + return 0; + } + } + if (readbuf) + { + errno = 0; + buffer.word = ptrace (PT_READ_I, PIDGET (inferior_ptid), + (PTRACE_TYPE_ARG3) (long) rounded_offset, 0); + if (errno) + return 0; + /* Copy appropriate bytes out of the buffer. */ + memcpy (readbuf, buffer.byte + (offset - rounded_offset), + partial_len); + } + return partial_len; + } case TARGET_OBJECT_UNWIND_TABLE: return -1; diff --git a/gdb/inftarg.c b/gdb/inftarg.c index e0b6a31e278..df3c5fe5edc 100644 --- a/gdb/inftarg.c +++ b/gdb/inftarg.c @@ -540,7 +540,7 @@ child_xfer_partial (struct target_ops *ops, enum target_object object, return child_xfer_memory (offset, readbuf, len, 0/*write*/, NULL, ops); if (writebuf) - return child_xfer_memory (offset, readbuf, len, 1/*write*/, + return child_xfer_memory (offset, (void *) writebuf, len, 1/*write*/, NULL, ops); return -1; -- 2.30.2