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-rw-r--r--src/od.c386
1 files changed, 187 insertions, 199 deletions
diff --git a/src/od.c b/src/od.c
index 3f16e3110..c0c4a0595 100644
--- a/src/od.c
+++ b/src/od.c
@@ -214,11 +214,13 @@ static size_t bytes_per_block;
It differs from *file_list only when *file_list is "-". */
static char const *input_filename;
-/* A NULL-terminated list of the file-arguments from the command line.
- If no file-arguments were specified, this variable is initialized
- to { "-", NULL }. */
+/* A NULL-terminated list of the file-arguments from the command line. */
static char const *const *file_list;
+/* Initializer for file_list if no file-arguments
+ were specified on the command line. */
+static char const *const default_file_list[] = {"-", NULL};
+
/* The input stream associated with the current file. */
static FILE *in_stream;
@@ -271,13 +273,15 @@ Usage: %s [OPTION]... [FILE]...\n\
or: %s --traditional [FILE] [[+]OFFSET [[+]LABEL]]\n\
"),
program_name, program_name);
- printf (_("\
-Write an unambiguous representation, octal bytes by default, of FILE\n\
-to standard output. With no FILE, or when FILE is -, read standard input.\n\
+ printf (_("\n\
+Write an unambiguous representation, octal bytes by default,\n\
+of FILE to standard output. With more than one FILE argument,\n\
+concatenate them in the listed order to form the input.\n\
+With no FILE, or when FILE is -, read standard input.\n\
\n\
-A, --address-radix=RADIX decide how file offsets are printed\n\
- -j, --skip-bytes=BYTES skip BYTES input bytes first on each file\n\
- -N, --read-bytes=BYTES limit dump to BYTES input bytes per file\n\
+ -j, --skip-bytes=BYTES skip BYTES input bytes first\n\
+ -N, --read-bytes=BYTES limit dump to BYTES input bytes\n\
-s, --strings[=BYTES] output strings of at least BYTES graphic chars\n\
-t, --format=TYPE select output format or formats\n\
-v, --output-duplicates do not use * to mark line suppression\n\
@@ -892,6 +896,88 @@ this system doesn't provide a %lu-byte floating point type"), s_orig, size);
return 0;
}
+/* Given a list of one or more input filenames FILE_LIST, set the global
+ file pointer IN_STREAM and the global string INPUT_FILENAME to the
+ first one that can be successfully opened. Modify FILE_LIST to
+ reference the next filename in the list. A file name of "-" is
+ interpreted as standard input. If any file open fails, give an error
+ message and return nonzero. */
+
+static int
+open_next_file (void)
+{
+ int err = 0;
+
+ do
+ {
+ input_filename = *file_list;
+ if (input_filename == NULL)
+ return err;
+ ++file_list;
+
+ if (STREQ (input_filename, "-"))
+ {
+ input_filename = _("standard input");
+ in_stream = stdin;
+ have_read_stdin = 1;
+ }
+ else
+ {
+ in_stream = fopen (input_filename, "r");
+ if (in_stream == NULL)
+ {
+ error (0, errno, "%s", input_filename);
+ err = 1;
+ }
+ }
+ }
+ while (in_stream == NULL);
+
+ if (limit_bytes_to_format && !flag_dump_strings)
+ setbuf (in_stream, NULL);
+ SET_BINARY (fileno (in_stream));
+
+ return err;
+}
+
+/* Test whether there have been errors on in_stream, and close it if
+ it is not standard input. Return nonzero if there has been an error
+ on in_stream or stdout; return zero otherwise. This function will
+ report more than one error only if both a read and a write error
+ have occurred. */
+
+static int
+check_and_close (void)
+{
+ int err = 0;
+
+ if (in_stream != NULL)
+ {
+ if (ferror (in_stream))
+ {
+ error (0, errno, "%s", input_filename);
+ if (in_stream != stdin)
+ fclose (in_stream);
+ err = 1;
+ }
+ else if (in_stream != stdin && fclose (in_stream) == EOF)
+ {
+ error (0, errno, "%s", input_filename);
+ err = 1;
+ }
+
+ in_stream = NULL;
+ }
+
+ if (ferror (stdout))
+ {
+ error (0, errno, _("standard output"));
+ err = 1;
+ }
+
+ return err;
+}
+
/* Decode the POSIX-style od format string S. Append the decoded
representation to the global array SPEC, reallocating SPEC if
necessary. Return zero if S is valid, nonzero otherwise. */
@@ -933,42 +1019,20 @@ decode_format_string (const char *s)
file pointer IN_STREAM to position N_SKIP in the concatenation of
those files. If any file operation fails or if there are fewer than
N_SKIP bytes in the combined input, give an error message and return
- nonzero. When possible, use seek- rather than read operations to
- advance IN_STREAM. A file name of "-" is interpreted as standard
- input. */
+ nonzero. When possible, use seek rather than read operations to
+ advance IN_STREAM. */
static int
skip (off_t n_skip)
{
- int err;
+ int err = 0;
- err = 0;
- for ( /* empty */ ; *file_list != NULL; ++file_list)
+ if (n_skip == 0)
+ return 0;
+
+ while (in_stream != NULL) /* EOF. */
{
struct stat file_stats;
- int j;
-
- if (STREQ (*file_list, "-"))
- {
- input_filename = _("standard input");
- in_stream = stdin;
- have_read_stdin = 1;
- }
- else
- {
- input_filename = *file_list;
- in_stream = fopen (input_filename, "r");
- if (in_stream == NULL)
- {
- error (0, errno, "%s", input_filename);
- err = 1;
- continue;
- }
- }
- SET_BINARY (fileno (in_stream));
-
- if (n_skip == 0)
- break;
/* First try seeking. For large offsets, this extra work is
worthwhile. If the offset is below some threshold it may be
@@ -980,58 +1044,60 @@ skip (off_t n_skip)
Try to do that by getting file's size using fstat.
But that will work only for regular files. */
- if (fstat (fileno (in_stream), &file_stats))
+ if (fstat (fileno (in_stream), &file_stats) == 0)
{
- error (0, errno, "%s", input_filename);
- err = 1;
- continue;
- }
+ /* The st_size field is valid only for regular files
+ (and for symbolic links, which cannot occur here).
+ If the number of bytes left to skip is at least
+ as large as the size of the current file, we can
+ decrement n_skip and go on to the next file. */
- /* The st_size field is valid only for regular files
- (and for symbolic links, which cannot occur here).
- If the number of bytes left to skip is at least as large as
- the size of the current file, we can decrement
- n_skip and go on to the next file. */
- if (S_ISREG (file_stats.st_mode))
- {
- if (file_stats.st_size <= n_skip)
+ if (S_ISREG (file_stats.st_mode) && file_stats.st_size <= n_skip)
{
n_skip -= file_stats.st_size;
- if (in_stream != stdin && fclose (in_stream) == EOF)
- {
- error (0, errno, "%s", input_filename);
- err = 1;
- }
- continue;
}
+
+ /* If the number of bytes left to skip is less than the size
+ of the current file, try seeking to the correct offset. */
+
+ else if (S_ISREG (file_stats.st_mode) &&
+ fseek (in_stream, n_skip, SEEK_CUR) == 0)
+ {
+ n_skip = 0;
+ }
+
+ /* If seek didn't work or wasn't attempted,
+ position the file pointer by reading. */
+
else
{
- if (0 <= lseek (fileno (in_stream), n_skip, SEEK_CUR))
+ char buf[BUFSIZ];
+ size_t n_bytes_read, n_bytes_to_read = BUFSIZ;
+
+ while (0 < n_skip)
{
- n_skip = 0;
- break;
+ if (n_skip < n_bytes_to_read)
+ n_bytes_to_read = n_skip;
+ n_bytes_read = fread (buf, 1, n_bytes_to_read, in_stream);
+ n_skip -= n_bytes_read;
+ if (n_bytes_read != n_bytes_to_read)
+ break;
}
}
- }
- /* Seek didn't work or wasn't attempted; position the file pointer
- by reading. */
+ if (n_skip == 0)
+ break;
+ }
- for (j = n_skip / BUFSIZ; 0 <= j; j--)
+ else /* cannot fstat() file */
{
- char buf[BUFSIZ];
- size_t n_bytes_to_read = (0 < j
- ? BUFSIZ
- : n_skip % BUFSIZ);
- size_t n_bytes_read;
- n_bytes_read = fread (buf, 1, n_bytes_to_read, in_stream);
- n_skip -= n_bytes_read;
- if (n_bytes_read != n_bytes_to_read)
- break;
+ error (0, errno, "%s", input_filename);
+ err = 1;
}
- if (n_skip == 0)
- break;
+ err |= check_and_close ();
+
+ err |= open_next_file ();
}
if (n_skip != 0)
@@ -1162,119 +1228,57 @@ write_block (off_t current_offset, off_t n_bytes,
first = 0;
}
-/* Test whether there have been errors on in_stream, and close it if
- it is not standard input. Return nonzero if there has been an error
- on in_stream or stdout; return zero otherwise. This function will
- report more than one error only if both a read and a write error
- have occurred. */
-
-static int
-check_and_close (void)
-{
- int err;
-
- err = 0;
- if (ferror (in_stream))
- {
- error (0, errno, "%s", input_filename);
- if (in_stream != stdin)
- fclose (in_stream);
- err = 1;
- }
- else if (in_stream != stdin && fclose (in_stream) == EOF)
- {
- error (0, errno, "%s", input_filename);
- err = 1;
- }
-
- if (ferror (stdout))
- {
- error (0, errno, _("standard output"));
- err = 1;
- }
-
- return err;
-}
-
/* Read a single byte into *C from the concatenation of the input files
named in the global array FILE_LIST. On the first call to this
function, the global variable IN_STREAM is expected to be an open
- stream associated with the input file *FILE_LIST. If IN_STREAM is
- at end-of-file, close it and update the global variables IN_STREAM,
- FILE_LIST, and INPUT_FILENAME so they correspond to the next file in
- the list. Then try to read a byte from the newly opened file.
- Repeat if necessary until *FILE_LIST is NULL. When EOF is reached
- for the last file in FILE_LIST, set *C to EOF and return. Subsequent
- calls do likewise. The return value is nonzero if any errors
- occured, zero otherwise. */
+ stream associated with the input file INPUT_FILENAME. If IN_STREAM
+ is at end-of-file, close it and update the global variables IN_STREAM
+ and INPUT_FILENAME so they correspond to the next file in the list.
+ Then try to read a byte from the newly opened file. Repeat if
+ necessary until EOF is reached for the last file in FILE_LIST, then
+ set *C to EOF and return. Subsequent calls do likewise. The return
+ value is nonzero if any errors occured, zero otherwise. */
static int
read_char (int *c)
{
- int err;
+ int err = 0;
- if (*file_list == NULL)
- {
- *c = EOF;
- return 0;
- }
+ *c = EOF;
- err = 0;
- while (1)
+ while (in_stream != NULL) /* EOF. */
{
*c = fgetc (in_stream);
if (*c != EOF)
- return err;
+ break;
err |= check_and_close ();
- do
- {
- ++file_list;
- if (*file_list == NULL)
- return err;
-
- if (STREQ (*file_list, "-"))
- {
- input_filename = _("standard input");
- in_stream = stdin;
- have_read_stdin = 1;
- }
- else
- {
- input_filename = *file_list;
- in_stream = fopen (input_filename, "r");
- if (in_stream == NULL)
- {
- error (0, errno, "%s", input_filename);
- err = 1;
- }
- }
- SET_BINARY (fileno (in_stream));
- }
- while (in_stream == NULL);
+ err |= open_next_file ();
}
+
+ return err;
}
/* Read N bytes into BLOCK from the concatenation of the input files
named in the global array FILE_LIST. On the first call to this
function, the global variable IN_STREAM is expected to be an open
- stream associated with the input file *FILE_LIST. On subsequent
- calls, if *FILE_LIST is NULL, don't modify BLOCK and return zero.
- If all N bytes cannot be read from IN_STREAM, close IN_STREAM and
- update the global variables IN_STREAM, FILE_LIST, and INPUT_FILENAME.
- Then try to read the remaining bytes from the newly opened file.
- Repeat if necessary until *FILE_LIST is NULL. Set *N_BYTES_IN_BUFFER
- to the number of bytes read. If an error occurs, it will be detected
- through ferror when the stream is about to be closed. If there is an
- error, give a message but continue reading as usual and return nonzero.
- Otherwise return zero. */
+ stream associated with the input file INPUT_FILENAME. If all N
+ bytes cannot be read from IN_STREAM, close IN_STREAM and update
+ the global variables IN_STREAM and INPUT_FILENAME. Then try to
+ read the remaining bytes from the newly opened file. Repeat if
+ necessary until EOF is reached for the last file in FILE_LIST.
+ On subsequent calls, don't modify BLOCK and return zero. Set
+ *N_BYTES_IN_BUFFER to the number of bytes read. If an error occurs,
+ it will be detected through ferror when the stream is about to be
+ closed. If there is an error, give a message but continue reading
+ as usual and return nonzero. Otherwise return zero. */
static int
read_block (size_t n, char *block, size_t *n_bytes_in_buffer)
{
- int err;
+ int err = 0;
assert (0 < n && n <= bytes_per_block);
@@ -1283,11 +1287,7 @@ read_block (size_t n, char *block, size_t *n_bytes_in_buffer)
if (n == 0)
return 0;
- if (*file_list == NULL)
- return 0; /* EOF. */
-
- err = 0;
- while (1)
+ while (in_stream != NULL) /* EOF. */
{
size_t n_needed;
size_t n_read;
@@ -1298,36 +1298,14 @@ read_block (size_t n, char *block, size_t *n_bytes_in_buffer)
*n_bytes_in_buffer += n_read;
if (n_read == n_needed)
- return err;
+ break;
err |= check_and_close ();
- do
- {
- ++file_list;
- if (*file_list == NULL)
- return err;
-
- if (STREQ (*file_list, "-"))
- {
- input_filename = _("standard input");
- in_stream = stdin;
- have_read_stdin = 1;
- }
- else
- {
- input_filename = *file_list;
- in_stream = fopen (input_filename, "r");
- if (in_stream == NULL)
- {
- error (0, errno, "%s", input_filename);
- err = 1;
- }
- }
- SET_BINARY (fileno (in_stream));
- }
- while (in_stream == NULL);
+ err |= open_next_file ();
}
+
+ return err;
}
/* Return the least common multiple of the sizes associated
@@ -1475,7 +1453,7 @@ dump (void)
format_address (current_offset, '\n');
- if (limit_bytes_to_format && current_offset > end_offset)
+ if (limit_bytes_to_format && current_offset >= end_offset)
err |= check_and_close ();
return err;
@@ -1593,7 +1571,7 @@ dump_strings (void)
}
/* We reach this point only if we search through
- (max_bytes_to_format - string_min) bytes before reachine EOF. */
+ (max_bytes_to_format - string_min) bytes before reaching EOF. */
free (buf);
@@ -1913,17 +1891,27 @@ it must be one character from [doxn]"),
}
if (n_files > 0)
- file_list = (char const *const *) &argv[optind];
+ {
+ /* Set the global pointer FILE_LIST so that it
+ references the first file-argument on the command-line. */
+
+ file_list = (char const *const *) &argv[optind];
+ }
else
{
- /* If no files were listed on the command line, set up the
- global array FILE_LIST so that it contains the null-terminated
- list of one name: "-". */
- static char const *const default_file_list[] = {"-", NULL};
+ /* No files were listed on the command line.
+ Set the global pointer FILE_LIST so that it
+ references the null-terminated list of one name: "-". */
file_list = default_file_list;
}
+ /* open the first input file */
+ err |= open_next_file ();
+ if (in_stream == NULL)
+ goto cleanup;
+
+ /* skip over any unwanted header bytes */
err |= skip (n_bytes_to_skip);
if (in_stream == NULL)
goto cleanup;