target_read_memory&co: no longer return target_xfer_status

Years ago, these functions used to return errno/EIO.  Later, through a
series of changes that intended to remove native/remote differences,
they ended up returning a target_xfer_status in disguise.

Unlike target_xfer_partial&co, the point of target_read_memory&co is
to either fully succeed or fail.  On error, they always return
TARGET_XFER_E_IO.  So there's no real point in casting the return of
target_read_memory to a target_xfer_status to pass it to memory_error.
Instead, it results in clearer code to simply decouple
target_read_memory&co's return from target_xfer_status.

This fixes build errors like this in C++ mode:

 ../../src/gdb/corefile.c: In function ‘void read_stack(CORE_ADDR, gdb_byte*, ssize_t)’:
 ../../src/gdb/corefile.c:276:34: error: invalid conversion from ‘int’ to ‘target_xfer_status’ [-fpermissive]
      memory_error (status, memaddr);
				   ^
 ../../src/gdb/corefile.c:216:1: error:   initializing argument 1 of ‘void memory_error(target_xfer_status, CORE_ADDR)’ [-fpermissive]

gdb/ChangeLog:
2015-10-27  Pedro Alves  <palves@redhat.com>

	* alpha-tdep.c (alpha_read_insn): Always pass TARGET_XFER_E_IO to
	memory_error.  Rename local 'status' to 'res'.
	* c-lang.c (c_get_string): Always pass TARGET_XFER_E_IO to
	memory_error.
	* corefile.c (read_stack, read_code, write_memory): Always pass
	TARGET_XFER_E_IO to memory_error.
	* disasm.c (dis_asm_memory_error): Always pass TARGET_XFER_E_IO to
	memory_error.  Rename parameter 'status' to 'err'.
	(dump_insns): Rename local 'status' to 'err'.
	* mips-tdep.c (mips_fetch_instruction): Rename parameter 'statusp'
	to 'errp'.  Rename local 'status' to 'err'.  Always pass
	TARGET_XFER_E_IO to memory_error.
	(mips_breakpoint_from_pc): Rename local 'status' to 'err'.
	* target.c (target_read_memory, target_read_raw_memory)
	(target_read_stack, target_read_code, target_write_memory)
	(target_write_raw_memory): Return -1 on error instead of
	TARGET_XFER_E_IO.
	* valprint.c (val_print_string): Rename local 'errcode' to 'err'.
	Always pass TARGET_XFER_E_IO to memory_error.  Update comment.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index e84a227..d7266e5 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,25 @@
+2015-10-27  Pedro Alves  <palves@redhat.com>
+
+       * alpha-tdep.c (alpha_read_insn): Always pass TARGET_XFER_E_IO to
+       memory_error.  Rename local 'status' to 'res'.
+       * c-lang.c (c_get_string): Always pass TARGET_XFER_E_IO to
+       memory_error.
+       * corefile.c (read_stack, read_code, write_memory): Always pass
+       TARGET_XFER_E_IO to memory_error.
+       * disasm.c (dis_asm_memory_error): Always pass TARGET_XFER_E_IO to
+       memory_error.  Rename parameter 'status' to 'err'.
+       (dump_insns): Rename local 'status' to 'err'.
+       * mips-tdep.c (mips_fetch_instruction): Rename parameter 'statusp'
+       to 'errp'.  Rename local 'status' to 'err'.  Always pass
+       TARGET_XFER_E_IO to memory_error.
+       (mips_breakpoint_from_pc): Rename local 'status' to 'err'.
+       * target.c (target_read_memory, target_read_raw_memory)
+       (target_read_stack, target_read_code, target_write_memory)
+       (target_write_raw_memory): Return -1 on error instead of
+       TARGET_XFER_E_IO.
+       * valprint.c (val_print_string): Rename local 'errcode' to 'err'.
+       Always pass TARGET_XFER_E_IO to memory_error.  Update comment.
+

 2015-10-27  Simon Marchi  <simon.marchi@polymtl.ca>
 
        * guile/guile-internal.h (gdbscm_with_guile): Change return
 2015-10-27  Simon Marchi  <simon.marchi@polymtl.ca>
 
        * guile/guile-internal.h (gdbscm_with_guile): Change return

diff --git a/gdb/alpha-tdep.c b/gdb/alpha-tdep.c
index 0696b6e..ca0e109 100644 (file)
--- a/gdb/alpha-tdep.c
+++ b/gdb/alpha-tdep.c
@@ -682,11 +682,11 @@ alpha_read_insn (struct gdbarch *gdbarch, CORE_ADDR pc)
 {
   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
   gdb_byte buf[ALPHA_INSN_SIZE];
 {
   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
   gdb_byte buf[ALPHA_INSN_SIZE];

-  int status;
+  int res;

 
 

-  status = target_read_memory (pc, buf, sizeof (buf));
-  if (status)
-    memory_error (status, pc);
+  res = target_read_memory (pc, buf, sizeof (buf));
+  if (res != 0)
+    memory_error (TARGET_XFER_E_IO, pc);

   return extract_unsigned_integer (buf, sizeof (buf), byte_order);
 }
 
   return extract_unsigned_integer (buf, sizeof (buf), byte_order);
 }
 

diff --git a/gdb/c-lang.c b/gdb/c-lang.c
index 6731b43..384783c 100644 (file)
--- a/gdb/c-lang.c
+++ b/gdb/c-lang.c
@@ -327,10 +327,10 @@ c_get_string (struct value *value, gdb_byte **buffer,
 
       err = read_string (addr, *length, width, fetchlimit,
                         byte_order, buffer, length);
 
       err = read_string (addr, *length, width, fetchlimit,
                         byte_order, buffer, length);

-      if (err)
+      if (err != 0)

        {
          xfree (*buffer);
        {
          xfree (*buffer);

-         memory_error (err, addr);
+         memory_error (TARGET_XFER_E_IO, addr);

        }
     }
 
        }
     }
 

diff --git a/gdb/corefile.c b/gdb/corefile.c
index 31301cf..596da33 100644 (file)
--- a/gdb/corefile.c
+++ b/gdb/corefile.c
@@ -273,7 +273,7 @@ read_stack (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
 
   status = target_read_stack (memaddr, myaddr, len);
   if (status != 0)
 
   status = target_read_stack (memaddr, myaddr, len);
   if (status != 0)

-    memory_error (status, memaddr);
+    memory_error (TARGET_XFER_E_IO, memaddr);

 }
 
 /* Same as target_read_code, but report an error if can't read.  */
 }
 
 /* Same as target_read_code, but report an error if can't read.  */


@@ -285,7 +285,7 @@ read_code (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
 
   status = target_read_code (memaddr, myaddr, len);
   if (status != 0)
 
   status = target_read_code (memaddr, myaddr, len);
   if (status != 0)

-    memory_error (status, memaddr);
+    memory_error (TARGET_XFER_E_IO, memaddr);

 }
 
 /* Read memory at MEMADDR of length LEN and put the contents in
 }
 
 /* Read memory at MEMADDR of length LEN and put the contents in


@@ -392,7 +392,7 @@ write_memory (CORE_ADDR memaddr,
 
   status = target_write_memory (memaddr, myaddr, len);
   if (status != 0)
 
   status = target_write_memory (memaddr, myaddr, len);
   if (status != 0)

-    memory_error (status, memaddr);
+    memory_error (TARGET_XFER_E_IO, memaddr);

 }
 
 /* Same as write_memory, but notify 'memory_changed' observers.  */
 }
 
 /* Same as write_memory, but notify 'memory_changed' observers.  */

diff --git a/gdb/disasm.c b/gdb/disasm.c
index 6e3d6c1..c17574e 100644 (file)
--- a/gdb/disasm.c
+++ b/gdb/disasm.c
@@ -129,10 +129,10 @@ dis_asm_read_memory (bfd_vma memaddr, gdb_byte *myaddr, unsigned int len,
 
 /* Like memory_error with slightly different parameters.  */
 static void
 
 /* Like memory_error with slightly different parameters.  */
 static void

-dis_asm_memory_error (int status, bfd_vma memaddr,
+dis_asm_memory_error (int err, bfd_vma memaddr,

                      struct disassemble_info *info)
 {
                      struct disassemble_info *info)
 {

-  memory_error (status, memaddr);
+  memory_error (TARGET_XFER_E_IO, memaddr);

 }
 
 /* Like print_address with slightly different parameters.  */
 }
 
 /* Like print_address with slightly different parameters.  */


@@ -230,7 +230,7 @@ dump_insns (struct gdbarch *gdbarch, struct ui_out *uiout,
         {
           CORE_ADDR old_pc = pc;
           bfd_byte data;
         {
           CORE_ADDR old_pc = pc;
           bfd_byte data;

-          int status;
+          int err;

           const char *spacer = "";
 
           /* Build the opcodes using a temporary stream so we can
           const char *spacer = "";
 
           /* Build the opcodes using a temporary stream so we can


@@ -242,9 +242,9 @@ dump_insns (struct gdbarch *gdbarch, struct ui_out *uiout,
           pc += gdbarch_print_insn (gdbarch, pc, di);
           for (;old_pc < pc; old_pc++)
             {
           pc += gdbarch_print_insn (gdbarch, pc, di);
           for (;old_pc < pc; old_pc++)
             {

-              status = (*di->read_memory_func) (old_pc, &data, 1, di);
-              if (status != 0)
-                (*di->memory_error_func) (status, old_pc, di);
+              err = (*di->read_memory_func) (old_pc, &data, 1, di);
+              if (err != 0)
+                (*di->memory_error_func) (err, old_pc, di);

               fprintf_filtered (opcode_stream, "%s%02x",
                                 spacer, (unsigned) data);
               spacer = " ";
               fprintf_filtered (opcode_stream, "%s%02x",
                                 spacer, (unsigned) data);
               spacer = " ";

diff --git a/gdb/mips-tdep.c b/gdb/mips-tdep.c
index 7cea832..6b5a1bd 100644 (file)
--- a/gdb/mips-tdep.c
+++ b/gdb/mips-tdep.c
@@ -1429,12 +1429,12 @@ mips_write_pc (struct regcache *regcache, CORE_ADDR pc)
 
 static ULONGEST
 mips_fetch_instruction (struct gdbarch *gdbarch,
 
 static ULONGEST
 mips_fetch_instruction (struct gdbarch *gdbarch,

-                       enum mips_isa isa, CORE_ADDR addr, int *statusp)
+                       enum mips_isa isa, CORE_ADDR addr, int *errp)

 {
   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
   gdb_byte buf[MIPS_INSN32_SIZE];
   int instlen;
 {
   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
   gdb_byte buf[MIPS_INSN32_SIZE];
   int instlen;

-  int status;
+  int err;

 
   switch (isa)
     {
 
   switch (isa)
     {


@@ -1450,13 +1450,13 @@ mips_fetch_instruction (struct gdbarch *gdbarch,
       internal_error (__FILE__, __LINE__, _("invalid ISA"));
       break;
     }
       internal_error (__FILE__, __LINE__, _("invalid ISA"));
       break;
     }

-  status = target_read_memory (addr, buf, instlen);
-  if (statusp != NULL)
-    *statusp = status;
-  if (status)
+  err = target_read_memory (addr, buf, instlen);
+  if (errp != NULL)
+    *errp = err;
+  if (err != 0)

     {
     {

-      if (statusp == NULL)
-       memory_error (status, addr);
+      if (errp == NULL)
+       memory_error (TARGET_XFER_E_IO, addr);

       return 0;
     }
   return extract_unsigned_integer (buf, instlen, byte_order);
       return 0;
     }
   return extract_unsigned_integer (buf, instlen, byte_order);


@@ -7118,12 +7118,13 @@ mips_breakpoint_from_pc (struct gdbarch *gdbarch,
          static gdb_byte micromips16_big_breakpoint[] = { 0x46, 0x85 };
          static gdb_byte micromips32_big_breakpoint[] = { 0, 0x5, 0, 0x7 };
          ULONGEST insn;
          static gdb_byte micromips16_big_breakpoint[] = { 0x46, 0x85 };
          static gdb_byte micromips32_big_breakpoint[] = { 0, 0x5, 0, 0x7 };
          ULONGEST insn;

-         int status;
+         int err;

          int size;
 
          int size;
 

-         insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, pc, &status);
-         size = status ? 2
-                       : mips_insn_size (ISA_MICROMIPS, insn) == 2 ? 2 : 4;
+         insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, pc, &err);
+         size = (err != 0
+                 ? 2 : (mips_insn_size (ISA_MICROMIPS, insn) == 2
+                        ? 2 : 4));

          *pcptr = unmake_compact_addr (pc);
          *lenptr = size;
          return (size == 2) ? micromips16_big_breakpoint
          *pcptr = unmake_compact_addr (pc);
          *lenptr = size;
          return (size == 2) ? micromips16_big_breakpoint

diff --git a/gdb/target.c b/gdb/target.c
index d7653c4..7ad2330 100644 (file)
--- a/gdb/target.c
+++ b/gdb/target.c
@@ -1380,7 +1380,7 @@ target_xfer_partial (struct target_ops *ops,
 
 /* Read LEN bytes of target memory at address MEMADDR, placing the
    results in GDB's memory at MYADDR.  Returns either 0 for success or
 
 /* Read LEN bytes of target memory at address MEMADDR, placing the
    results in GDB's memory at MYADDR.  Returns either 0 for success or

-   TARGET_XFER_E_IO if any error occurs.
+   -1 if any error occurs.

 
    If an error occurs, no guarantee is made about the contents of the data at
    MYADDR.  In particular, the caller should not depend upon partial reads
 
    If an error occurs, no guarantee is made about the contents of the data at
    MYADDR.  In particular, the caller should not depend upon partial reads


@@ -1399,7 +1399,7 @@ target_read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
                   myaddr, memaddr, len) == len)
     return 0;
   else
                   myaddr, memaddr, len) == len)
     return 0;
   else

-    return TARGET_XFER_E_IO;
+    return -1;

 }
 
 /* See target/target.h.  */
 }
 
 /* See target/target.h.  */


@@ -1431,7 +1431,7 @@ target_read_raw_memory (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
                   myaddr, memaddr, len) == len)
     return 0;
   else
                   myaddr, memaddr, len) == len)
     return 0;
   else

-    return TARGET_XFER_E_IO;
+    return -1;

 }
 
 /* Like target_read_memory, but specify explicitly that this is a read from
 }
 
 /* Like target_read_memory, but specify explicitly that this is a read from


@@ -1446,7 +1446,7 @@ target_read_stack (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
                   myaddr, memaddr, len) == len)
     return 0;
   else
                   myaddr, memaddr, len) == len)
     return 0;
   else

-    return TARGET_XFER_E_IO;
+    return -1;

 }
 
 /* Like target_read_memory, but specify explicitly that this is a read from
 }
 
 /* Like target_read_memory, but specify explicitly that this is a read from


@@ -1461,14 +1461,14 @@ target_read_code (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
                   myaddr, memaddr, len) == len)
     return 0;
   else
                   myaddr, memaddr, len) == len)
     return 0;
   else

-    return TARGET_XFER_E_IO;
+    return -1;

 }
 
 /* Write LEN bytes from MYADDR to target memory at address MEMADDR.
 }
 
 /* Write LEN bytes from MYADDR to target memory at address MEMADDR.

-   Returns either 0 for success or TARGET_XFER_E_IO if any
-   error occurs.  If an error occurs, no guarantee is made about how
-   much data got written.  Callers that can deal with partial writes
-   should call target_write.  */
+   Returns either 0 for success or -1 if any error occurs.  If an
+   error occurs, no guarantee is made about how much data got written.
+   Callers that can deal with partial writes should call
+   target_write.  */

 
 int
 target_write_memory (CORE_ADDR memaddr, const gdb_byte *myaddr, ssize_t len)
 
 int
 target_write_memory (CORE_ADDR memaddr, const gdb_byte *myaddr, ssize_t len)


@@ -1479,14 +1479,14 @@ target_write_memory (CORE_ADDR memaddr, const gdb_byte *myaddr, ssize_t len)
                    myaddr, memaddr, len) == len)
     return 0;
   else
                    myaddr, memaddr, len) == len)
     return 0;
   else

-    return TARGET_XFER_E_IO;
+    return -1;

 }
 
 /* Write LEN bytes from MYADDR to target raw memory at address
 }
 
 /* Write LEN bytes from MYADDR to target raw memory at address

-   MEMADDR.  Returns either 0 for success or TARGET_XFER_E_IO
-   if any error occurs.  If an error occurs, no guarantee is made
-   about how much data got written.  Callers that can deal with
-   partial writes should call target_write.  */
+   MEMADDR.  Returns either 0 for success or -1 if any error occurs.
+   If an error occurs, no guarantee is made about how much data got
+   written.  Callers that can deal with partial writes should call
+   target_write.  */

 
 int
 target_write_raw_memory (CORE_ADDR memaddr, const gdb_byte *myaddr, ssize_t len)
 
 int
 target_write_raw_memory (CORE_ADDR memaddr, const gdb_byte *myaddr, ssize_t len)


@@ -1497,7 +1497,7 @@ target_write_raw_memory (CORE_ADDR memaddr, const gdb_byte *myaddr, ssize_t len)
                    myaddr, memaddr, len) == len)
     return 0;
   else
                    myaddr, memaddr, len) == len)
     return 0;
   else

-    return TARGET_XFER_E_IO;
+    return -1;

 }
 
 /* Fetch the target's memory map.  */
 }
 
 /* Fetch the target's memory map.  */

diff --git a/gdb/valprint.c b/gdb/valprint.c
index 7e74856..7f891c9 100644 (file)
--- a/gdb/valprint.c
+++ b/gdb/valprint.c
@@ -2737,7 +2737,7 @@ val_print_string (struct type *elttype, const char *encoding,
                  const struct value_print_options *options)
 {
   int force_ellipsis = 0;      /* Force ellipsis to be printed if nonzero.  */
                  const struct value_print_options *options)
 {
   int force_ellipsis = 0;      /* Force ellipsis to be printed if nonzero.  */

-  int errcode;                 /* Errno returned from bad reads.  */
+  int err;                     /* Non-zero if we got a bad read.  */

   int found_nul;               /* Non-zero if we found the nul char.  */
   unsigned int fetchlimit;     /* Maximum number of chars to print.  */
   int bytes_read;
   int found_nul;               /* Non-zero if we found the nul char.  */
   unsigned int fetchlimit;     /* Maximum number of chars to print.  */
   int bytes_read;


@@ -2758,8 +2758,8 @@ val_print_string (struct type *elttype, const char *encoding,
   fetchlimit = (len == -1 ? options->print_max : min (len,
                                                      options->print_max));
 
   fetchlimit = (len == -1 ? options->print_max : min (len,
                                                      options->print_max));
 

-  errcode = read_string (addr, len, width, fetchlimit, byte_order,
-                        &buffer, &bytes_read);
+  err = read_string (addr, len, width, fetchlimit, byte_order,
+                    &buffer, &bytes_read);

   old_chain = make_cleanup (xfree, buffer);
 
   addr += bytes_read;
   old_chain = make_cleanup (xfree, buffer);
 
   addr += bytes_read;


@@ -2787,7 +2787,7 @@ val_print_string (struct type *elttype, const char *encoding,
          && extract_unsigned_integer (peekbuf, width, byte_order) != 0)
        force_ellipsis = 1;
     }
          && extract_unsigned_integer (peekbuf, width, byte_order) != 0)
        force_ellipsis = 1;
     }

-  else if ((len >= 0 && errcode != 0) || (len > bytes_read / width))
+  else if ((len >= 0 && err != 0) || (len > bytes_read / width))

     {
       /* Getting an error when we have a requested length, or fetching less
          than the number of characters actually requested, always make us
     {
       /* Getting an error when we have a requested length, or fetching less
          than the number of characters actually requested, always make us


@@ -2798,17 +2798,17 @@ val_print_string (struct type *elttype, const char *encoding,
   /* If we get an error before fetching anything, don't print a string.
      But if we fetch something and then get an error, print the string
      and then the error message.  */
   /* If we get an error before fetching anything, don't print a string.
      But if we fetch something and then get an error, print the string
      and then the error message.  */

-  if (errcode == 0 || bytes_read > 0)
+  if (err == 0 || bytes_read > 0)

     {
       LA_PRINT_STRING (stream, elttype, buffer, bytes_read / width,
                       encoding, force_ellipsis, options);
     }
 
     {
       LA_PRINT_STRING (stream, elttype, buffer, bytes_read / width,
                       encoding, force_ellipsis, options);
     }
 

-  if (errcode != 0)
+  if (err != 0)

     {
       char *str;
 
     {
       char *str;
 

-      str = memory_error_message (errcode, gdbarch, addr);
+      str = memory_error_message (TARGET_XFER_E_IO, gdbarch, addr);

       make_cleanup (xfree, str);
 
       fprintf_filtered (stream, "<error: ");
       make_cleanup (xfree, str);
 
       fprintf_filtered (stream, "<error: ");