/* Print values for GDB, the GNU debugger.
Copyright (C) 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
- 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
- Free Software Foundation, Inc.
+ 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
+ 2009 Free Software Foundation, Inc.
This file is part of GDB.
return (nread);
}
-/* Print a string from the inferior, starting at ADDR and printing up to LEN
- characters, of WIDTH bytes a piece, to STREAM. If LEN is -1, printing
- stops at the first null byte, otherwise printing proceeds (including null
- bytes) until either print_max or LEN characters have been printed,
- whichever is smaller. */
-
-/* FIXME: Use target_read_string. */
+/* Read a string from the inferior, at ADDR, with LEN characters of WIDTH bytes
+ each. Fetch at most FETCHLIMIT characters. BUFFER will be set to a newly
+ allocated buffer containing the string, which the caller is responsible to
+ free, and BYTES_READ will be set to the number of bytes read. Returns 0 on
+ success, or errno on failure.
-int
-val_print_string (CORE_ADDR addr, int len, int width, struct ui_file *stream,
- const struct value_print_options *options)
-{
- int force_ellipsis = 0; /* Force ellipsis to be printed if nonzero. */
- int errcode; /* Errno returned from bad reads. */
- unsigned int fetchlimit; /* Maximum number of chars to print. */
- unsigned int nfetch; /* Chars to fetch / chars fetched. */
- unsigned int chunksize; /* Size of each fetch, in chars. */
- gdb_byte *buffer = NULL; /* Dynamically growable fetch buffer. */
- gdb_byte *bufptr; /* Pointer to next available byte in buffer. */
- gdb_byte *limit; /* First location past end of fetch buffer. */
- struct cleanup *old_chain = NULL; /* Top of the old cleanup chain. */
- int found_nul; /* Non-zero if we found the nul char */
+ If LEN > 0, reads exactly LEN characters (including eventual NULs in
+ the middle or end of the string). If LEN is -1, stops at the first
+ null character (not necessarily the first null byte) up to a maximum
+ of FETCHLIMIT characters. Set FETCHLIMIT to UINT_MAX to read as many
+ characters as possible from the string.
- /* First we need to figure out the limit on the number of characters we are
- going to attempt to fetch and print. This is actually pretty simple. If
- LEN >= zero, then the limit is the minimum of LEN and print_max. If
- LEN is -1, then the limit is print_max. This is true regardless of
- whether print_max is zero, UINT_MAX (unlimited), or something in between,
- because finding the null byte (or available memory) is what actually
- limits the fetch. */
+ Unless an exception is thrown, BUFFER will always be allocated, even on
+ failure. In this case, some characters might have been read before the
+ failure happened. Check BYTES_READ to recognize this situation.
- fetchlimit = (len == -1 ? options->print_max : min (len, options->print_max));
+ Note: There was a FIXME asking to make this code use target_read_string,
+ but this function is more general (can read past null characters, up to
+ given LEN). Besides, it is used much more often than target_read_string
+ so it is more tested. Perhaps callers of target_read_string should use
+ this function instead? */
- /* Now decide how large of chunks to try to read in one operation. This
+int
+read_string (CORE_ADDR addr, int len, int width, unsigned int fetchlimit,
+ gdb_byte **buffer, int *bytes_read)
+{
+ int found_nul; /* Non-zero if we found the nul char. */
+ int errcode; /* Errno returned from bad reads. */
+ unsigned int nfetch; /* Chars to fetch / chars fetched. */
+ unsigned int chunksize; /* Size of each fetch, in chars. */
+ gdb_byte *bufptr; /* Pointer to next available byte in buffer. */
+ gdb_byte *limit; /* First location past end of fetch buffer. */
+ struct cleanup *old_chain = NULL; /* Top of the old cleanup chain. */
+
+ /* Decide how large of chunks to try to read in one operation. This
is also pretty simple. If LEN >= zero, then we want fetchlimit chars,
so we might as well read them all in one operation. If LEN is -1, we
- are looking for a null terminator to end the fetching, so we might as
+ are looking for a NUL terminator to end the fetching, so we might as
well read in blocks that are large enough to be efficient, but not so
large as to be slow if fetchlimit happens to be large. So we choose the
minimum of 8 and fetchlimit. We used to use 200 instead of 8 but
chunksize = (len == -1 ? min (8, fetchlimit) : fetchlimit);
- /* Loop until we either have all the characters to print, or we encounter
- some error, such as bumping into the end of the address space. */
+ /* Loop until we either have all the characters, or we encounter
+ some error, such as bumping into the end of the address space. */
found_nul = 0;
old_chain = make_cleanup (null_cleanup, 0);
if (len > 0)
{
- buffer = (gdb_byte *) xmalloc (len * width);
- bufptr = buffer;
- old_chain = make_cleanup (xfree, buffer);
+ *buffer = (gdb_byte *) xmalloc (len * width);
+ bufptr = *buffer;
+ old_chain = make_cleanup (xfree, *buffer);
nfetch = partial_memory_read (addr, bufptr, len * width, &errcode)
/ width;
else if (len == -1)
{
unsigned long bufsize = 0;
+
+ *buffer = NULL;
+
do
{
QUIT;
nfetch = min (chunksize, fetchlimit - bufsize);
- if (buffer == NULL)
- buffer = (gdb_byte *) xmalloc (nfetch * width);
+ if (*buffer == NULL)
+ *buffer = (gdb_byte *) xmalloc (nfetch * width);
else
{
discard_cleanups (old_chain);
- buffer = (gdb_byte *) xrealloc (buffer, (nfetch + bufsize) * width);
+ *buffer = (gdb_byte *) xrealloc (*buffer,
+ (nfetch + bufsize) * width);
}
- old_chain = make_cleanup (xfree, buffer);
- bufptr = buffer + bufsize * width;
+ old_chain = make_cleanup (xfree, *buffer);
+ bufptr = *buffer + bufsize * width;
bufsize += nfetch;
- /* Read as much as we can. */
+ /* Read as much as we can. */
nfetch = partial_memory_read (addr, bufptr, nfetch * width, &errcode)
- / width;
+ / width;
- /* Scan this chunk for the null byte that terminates the string
+ /* Scan this chunk for the null character that terminates the string
to print. If found, we don't need to fetch any more. Note
that bufptr is explicitly left pointing at the next character
- after the null byte, or at the next character after the end of
- the buffer. */
+ after the null character, or at the next character after the end
+ of the buffer. */
limit = bufptr + nfetch * width;
while (bufptr < limit)
if (c == 0)
{
/* We don't care about any error which happened after
- the NULL terminator. */
+ the NUL terminator. */
errcode = 0;
found_nul = 1;
break;
}
}
while (errcode == 0 /* no error */
- && bufptr - buffer < fetchlimit * width /* no overrun */
- && !found_nul); /* haven't found nul yet */
+ && bufptr - *buffer < fetchlimit * width /* no overrun */
+ && !found_nul); /* haven't found NUL yet */
}
else
- { /* length of string is really 0! */
- buffer = bufptr = NULL;
+ { /* Length of string is really 0! */
+ /* We always allocate *buffer. */
+ *buffer = bufptr = xmalloc (1);
errcode = 0;
}
/* bufptr and addr now point immediately beyond the last byte which we
consider part of the string (including a '\0' which ends the string). */
+ *bytes_read = bufptr - *buffer;
+
+ QUIT;
+
+ discard_cleanups (old_chain);
+
+ return errcode;
+}
+
+/* Print a string from the inferior, starting at ADDR and printing up to LEN
+ characters, of WIDTH bytes a piece, to STREAM. If LEN is -1, printing
+ stops at the first null byte, otherwise printing proceeds (including null
+ bytes) until either print_max or LEN characters have been printed,
+ whichever is smaller. */
+
+int
+val_print_string (CORE_ADDR addr, int len, int width, struct ui_file *stream,
+ 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 found_nul; /* Non-zero if we found the nul char */
+ unsigned int fetchlimit; /* Maximum number of chars to print. */
+ int bytes_read;
+ gdb_byte *buffer = NULL; /* Dynamically growable fetch buffer. */
+ struct cleanup *old_chain = NULL; /* Top of the old cleanup chain. */
+
+ /* First we need to figure out the limit on the number of characters we are
+ going to attempt to fetch and print. This is actually pretty simple. If
+ LEN >= zero, then the limit is the minimum of LEN and print_max. If
+ LEN is -1, then the limit is print_max. This is true regardless of
+ whether print_max is zero, UINT_MAX (unlimited), or something in between,
+ because finding the null byte (or available memory) is what actually
+ limits the fetch. */
+
+ fetchlimit = (len == -1 ? options->print_max : min (len, options->print_max));
+
+ errcode = read_string (addr, len, width, fetchlimit, &buffer, &bytes_read);
+ old_chain = make_cleanup (xfree, buffer);
+
+ addr += bytes_read;
/* We now have either successfully filled the buffer to fetchlimit, or
- terminated early due to an error or finding a null char when LEN is -1. */
+ terminated early due to an error or finding a null char when LEN is -1. */
+
+ /* Determine found_nul by looking at the last character read. */
+ found_nul = extract_unsigned_integer (buffer + bytes_read - width, width) == 0;
if (len == -1 && !found_nul)
{
gdb_byte *peekbuf;
- /* We didn't find a null terminator we were looking for. Attempt
+ /* We didn't find a NUL terminator we were looking for. Attempt
to peek at the next character. If not successful, or it is not
a null byte, then force ellipsis to be printed. */
&& extract_unsigned_integer (peekbuf, width) != 0)
force_ellipsis = 1;
}
- else if ((len >= 0 && errcode != 0) || (len > (bufptr - buffer) / width))
+ else if ((len >= 0 && errcode != 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
- print ellipsis. */
+ print ellipsis. */
force_ellipsis = 1;
}
- QUIT;
-
/* 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 || bufptr > buffer)
+ if (errcode == 0 || bytes_read > 0)
{
if (options->addressprint)
{
fputs_filtered (" ", stream);
}
- LA_PRINT_STRING (stream, buffer, (bufptr - buffer) / width, width, force_ellipsis, options);
+ LA_PRINT_STRING (stream, buffer, bytes_read / width, width, force_ellipsis, options);
}
if (errcode != 0)
fprintf_filtered (stream, ": %s>", safe_strerror (errcode));
}
}
+
gdb_flush (stream);
do_cleanups (old_chain);
- return ((bufptr - buffer) / width);
+
+ return (bytes_read / width);
}
\f
+/* The 'set input-radix' command writes to this auxiliary variable.
+ If the requested radix is valid, INPUT_RADIX is updated; otherwise,
+ it is left unchanged. */
+
+static unsigned input_radix_1 = 10;
+
/* Validate an input or output radix setting, and make sure the user
knows what they really did here. Radix setting is confusing, e.g.
setting the input radix to "10" never changes it! */
static void
set_input_radix (char *args, int from_tty, struct cmd_list_element *c)
{
- set_input_radix_1 (from_tty, input_radix);
+ set_input_radix_1 (from_tty, input_radix_1);
}
static void
if (radix < 2)
{
- /* FIXME: cagney/2002-03-17: This needs to revert the bad radix
- value. */
+ input_radix_1 = input_radix;
error (_("Nonsense input radix ``decimal %u''; input radix unchanged."),
radix);
}
- input_radix = radix;
+ input_radix_1 = input_radix = radix;
if (from_tty)
{
printf_filtered (_("Input radix now set to decimal %u, hex %x, octal %o.\n"),
}
}
+/* The 'set output-radix' command writes to this auxiliary variable.
+ If the requested radix is valid, OUTPUT_RADIX is updated,
+ otherwise, it is left unchanged. */
+
+static unsigned output_radix_1 = 10;
+
static void
set_output_radix (char *args, int from_tty, struct cmd_list_element *c)
{
- set_output_radix_1 (from_tty, output_radix);
+ set_output_radix_1 (from_tty, output_radix_1);
}
static void
user_print_options.output_format = 'o'; /* octal */
break;
default:
- /* FIXME: cagney/2002-03-17: This needs to revert the bad radix
- value. */
+ output_radix_1 = output_radix;
error (_("Unsupported output radix ``decimal %u''; output radix unchanged."),
radix);
}
- output_radix = radix;
+ output_radix_1 = output_radix = radix;
if (from_tty)
{
printf_filtered (_("Output radix now set to decimal %u, hex %x, octal %o.\n"),
show_addressprint,
&setprintlist, &showprintlist);
- add_setshow_uinteger_cmd ("input-radix", class_support, &input_radix, _("\
+ add_setshow_zuinteger_cmd ("input-radix", class_support, &input_radix_1,
+ _("\
Set default input radix for entering numbers."), _("\
Show default input radix for entering numbers."), NULL,
- set_input_radix,
- show_input_radix,
- &setlist, &showlist);
+ set_input_radix,
+ show_input_radix,
+ &setlist, &showlist);
- add_setshow_uinteger_cmd ("output-radix", class_support, &output_radix, _("\
+ add_setshow_zuinteger_cmd ("output-radix", class_support, &output_radix_1,
+ _("\
Set default output radix for printing of values."), _("\
Show default output radix for printing of values."), NULL,
- set_output_radix,
- show_output_radix,
- &setlist, &showlist);
+ set_output_radix,
+ show_output_radix,
+ &setlist, &showlist);
/* The "set radix" and "show radix" commands are special in that
they are like normal set and show commands but allow two normally