/*---------------------------------------------------------------------.
| Execute the conversion sequence for a recoding TASK, using several |
-| passes with two alternating memory buffers or intermediate files. |
+| passes with two alternating memory buffers or intermediate files, or |
+| forking for each step and interconnecting the processes with pipes. |
| This routine assumes at least one needed recoding step. |
`---------------------------------------------------------------------*/
RECODE_CONST_REQUEST request = task->request;
struct recode_subtask subtask_block;
RECODE_SUBTASK subtask = &subtask_block;
+
+ int pipe_pair[2]; /* pair of file descriptors for a pipe */
+ pid_t wait_status; /* status returned by wait() */
+
struct recode_read_write_text input;
struct recode_read_write_text output;
-
- memset (subtask, 0, sizeof (struct recode_subtask));
memset (&input, 0, sizeof (struct recode_read_write_text));
memset (&output, 0, sizeof (struct recode_read_write_text));
+
+ memset (subtask, 0, sizeof (struct recode_subtask));
subtask->task = task;
+ subtask->input = task->input;
+
+ /* Prepare the first input file. */
+
+ if (subtask->input.name)
+ {
+ if (!*subtask->input.name)
+ subtask->input.file = stdin;
+ else if (subtask->input.file = fopen (subtask->input.name, "r"),
+ subtask->input.file == NULL)
+ {
+ recode_perror (NULL, "fopen (%s)", subtask->input.name);
+ recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ SUBTASK_RETURN (subtask);
+ }
+ }
/* Execute one pass for each step of the sequence. */
+ int child_process = -1; /* child process number, -1 if process has not forked */
for (unsigned sequence_index = 0;
sequence_index < (unsigned)request->sequence_length
&& task->error_so_far < task->abort_level;
sequence_index++)
{
- RECODE_CONST_STEP step = request->sequence_array + sequence_index;
- subtask->step = step;
-
- /* Select the input text for this step. */
-
- if (sequence_index == 0)
- {
- subtask->input = task->input;
-
- if (subtask->input.name)
- {
- if (!*subtask->input.name)
- subtask->input.file = stdin;
- else if (subtask->input.file = fopen (subtask->input.name, "r"),
- subtask->input.file == NULL)
- {
- recode_perror (NULL, "fopen (%s)", subtask->input.name);
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- goto exit;
- }
- }
- }
- else
- {
- subtask->input.buffer = input.buffer;
- subtask->input.cursor = input.buffer;
- subtask->input.limit = input.cursor;
- subtask->input.file = input.file;
+ child_process = -1;
+ subtask->output = task->output;
- if (strategy == RECODE_SEQUENCE_WITH_FILES &&
- fseek (subtask->input.file, 0L, SEEK_SET) != 0)
- {
- recode_perror (NULL, "fseek (%s)", subtask->input.name);
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- goto exit;
- }
- }
+ if (strategy == RECODE_SEQUENCE_IN_MEMORY || strategy == RECODE_SEQUENCE_WITH_FILES)
+ if (sequence_index > 0)
+ {
+ /* Select the input text for this step. */
+
+ subtask->input.buffer = input.buffer;
+ subtask->input.cursor = input.buffer;
+ subtask->input.limit = input.cursor;
+ subtask->input.file = input.file;
+
+ if (strategy == RECODE_SEQUENCE_WITH_FILES &&
+ fseek (subtask->input.file, 0L, SEEK_SET) != 0)
+ {
+ recode_perror (NULL, "fseek (%s)", subtask->input.name);
+ recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ goto exit;
+ }
+ }
/* Select the output text for this step. */
if (sequence_index < (unsigned)request->sequence_length - 1)
{
- subtask->output = output;
-
switch (strategy)
{
case RECODE_SEQUENCE_IN_MEMORY:
}
break;
+#if HAVE_PIPE
+ case RECODE_SEQUENCE_WITH_PIPE:
+ /* Create all subprocesses, from the first to the last, and
+ interconnect them. */
+
+ if (pipe (pipe_pair) < 0)
+ {
+ recode_perror (NULL, "pipe ()");
+ recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ SUBTASK_RETURN (subtask);
+ }
+ if (child_process = fork (), child_process < 0)
+ {
+ recode_perror (NULL, "fork ()");
+ recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ SUBTASK_RETURN (subtask);
+ }
+ if (child_process == 0)
+ {
+ /* The child executes its recoding step, reading from the
+ current input file and writing to the pipe; then it exits. */
+
+ if (close (pipe_pair[0]) < 0)
+ {
+ recode_perror (NULL, "close ()");
+ recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ }
+ if (subtask->output.file = fdopen (pipe_pair[1], "w"),
+ subtask->output.file == NULL)
+ {
+ recode_perror (NULL, "fdopen ()");
+ recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ }
+ }
+ else
+ {
+ /* The parent redirects the current input file to the pipe. */
+
+ if (dup2 (pipe_pair[0], fileno (subtask->input.file)) < 0)
+ {
+ recode_perror (NULL, "dup2 ()");
+ recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ SUBTASK_RETURN (subtask);
+ }
+ if (close (pipe_pair[0]) < 0)
+ {
+ recode_perror (NULL, "close ()");
+ recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ SUBTASK_RETURN (subtask);
+ }
+ if (close (pipe_pair[1]) < 0)
+ {
+ recode_perror (NULL, "close ()");
+ recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ SUBTASK_RETURN (subtask);
+ }
+ }
+ break;
+#endif
+
default: /* Should never happen */
recode_if_nogo (RECODE_INTERNAL_ERROR, subtask);
break;
}
else
{
- subtask->output = task->output;
+ /* Prepare the final output file. */
if (subtask->output.name)
{
{
recode_perror (NULL, "fopen (%s)", subtask->output.name);
recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- goto exit;
+ goto exit;
}
}
}
/* Execute one recoding step. */
- (*step->transform_routine) (subtask);
+ if (child_process <= 0)
+ {
+ RECODE_CONST_STEP step; /* pointer into single_steps */
- /* Post-step clean up. */
+ step = request->sequence_array + sequence_index;
+ subtask->step = step;
+ (*step->transform_routine) (subtask);
+
+ if (strategy == RECODE_SEQUENCE_WITH_PIPE)
+ break; /* parent process: escape from loop */
+ }
- if (subtask->input.file)
+ if (strategy != RECODE_SEQUENCE_WITH_PIPE)
{
- FILE *fp = subtask->input.file;
+ /* Post-step clean up. */
- subtask->input.file = NULL;
- if (fclose (fp) != 0)
+ if (subtask->input.file)
{
- recode_perror (NULL, "fclose (%s)", subtask->input.name);
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- goto exit;
- }
- }
+ FILE *fp = subtask->input.file;
- if (sequence_index == 0)
- {
- task->input = subtask->input;
- memset (&subtask->input, 0, sizeof (struct recode_read_write_text));
- }
+ subtask->input.file = NULL;
+ if (fclose (fp) != 0)
+ {
+ recode_perror (NULL, "fclose (%s)", subtask->input.name);
+ recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ goto exit;
+ }
+ }
- /* Prepare for next step. */
+ /* Prepare for next step. */
- task->swap_input = RECODE_SWAP_UNDECIDED;
+ task->swap_input = RECODE_SWAP_UNDECIDED;
- if (sequence_index < (unsigned)request->sequence_length - 1)
- {
- output = input;
- input = subtask->output;
+ if (sequence_index < (unsigned)request->sequence_length - 1)
+ {
+ output = input;
+ input = subtask->output;
+ }
}
}
if (subtask->input.file && fclose (subtask->input.file) != 0)
{
- recode_perror (NULL, "fclose (%s)", subtask->input.name);
+ recode_perror (NULL, "fclose (%s)", subtask->input.name ? subtask->input.name : "stdin");
recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
}
if (subtask->output.file && fclose (subtask->output.file) != 0)
{
- recode_perror (NULL, "fclose (%s)", subtask->output.name);
+ recode_perror (NULL, "fclose (%s)", subtask->output.name ? subtask->output.name : "stdout");
recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
}
- free (input.buffer);
- free (output.buffer);
-
- task->output = subtask->output;
- SUBTASK_RETURN (subtask);
-}
#if HAVE_PIPE
-
-/*-------------------------------------------------------------------------.
-| Execute the conversion sequence, forking the program many times for all |
-| elementary steps, interconnecting them with pipes. This routine assumes |
-| that more than one recoding step is needed. |
-`-------------------------------------------------------------------------*/
-
-static bool
-perform_pipe_sequence (RECODE_TASK task)
-{
- RECODE_CONST_REQUEST request = task->request;
- struct recode_subtask subtask_block;
- RECODE_SUBTASK subtask = &subtask_block;
-
- RECODE_CONST_STEP step; /* pointer into single_steps */
-
- int pipe_pair[2]; /* pair of file descriptors for a pipe */
- int child_process; /* child process number, zero if child */
- pid_t wait_status; /* status returned by wait() */
-
- memset (subtask, 0, sizeof (struct recode_subtask));
- subtask->task = task;
- subtask->input = task->input;
- subtask->output = task->output;
-
- /* Prepare the final input file. */
-
- if (!*subtask->input.name)
- subtask->input.file = stdin;
- else if (subtask->input.file = fopen (subtask->input.name, "r"),
- subtask->input.file == NULL)
+ if (strategy == RECODE_SEQUENCE_WITH_PIPE)
{
- recode_perror (NULL, "fopen (%s)", subtask->input.name);
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- SUBTASK_RETURN (subtask);
- }
-
- /* Create all subprocesses, from the first to the last, and
- interconnect them. */
+ /* Child process exits here. */
- for (unsigned sequence_index = 0;
- sequence_index < (unsigned)request->sequence_length - 1;
- sequence_index++)
- {
- if (pipe (pipe_pair) < 0)
- {
- recode_perror (NULL, "pipe ()");
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- SUBTASK_RETURN (subtask);
- }
- if (child_process = fork (), child_process < 0)
- {
- recode_perror (NULL, "fork ()");
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- SUBTASK_RETURN (subtask);
- }
if (child_process == 0)
+ exit (task->error_so_far < task->fail_level ? EXIT_SUCCESS
+ : EXIT_FAILURE);
+ else
{
- /* The child executes its recoding step, reading from the
- current input file and writing to the pipe; then it exits. */
+ /* Wait on all children, mainly to avoid synchronisation problems on
+ output file contents, but also to reduce the number of zombie
+ processes in case the user recodes many files at once. */
- if (close (pipe_pair[0]) < 0)
+ while (wait (&wait_status) > 0)
{
- recode_perror (NULL, "close ()");
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- }
- if (subtask->output.file = fdopen (pipe_pair[1], "w"),
- subtask->output.file == NULL)
- {
- recode_perror (NULL, "fdopen ()");
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- }
+ /* Diagnose and abort on any abnormally terminating child. */
- step = request->sequence_array + sequence_index;
- subtask->step = step;
- (*step->transform_routine) (subtask);
+ if (!(WIFEXITED (wait_status)
+ || (WIFSIGNALED (wait_status)
+ && WTERMSIG (wait_status) == SIGPIPE)))
+ {
+ recode_error (NULL, _("Child process wait status is 0x%0.2x"),
+ wait_status);
+ recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ SUBTASK_RETURN (subtask);
+ }
- if (subtask->input.file && fclose (subtask->input.file) != 0)
- {
- recode_perror (NULL, "fclose (%s)", subtask->input.name ? subtask->input.name : "stdin");
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
+ /* Check for a nonzero exit from the terminating child. */
+
+ if (WIFEXITED (wait_status)
+ ? WEXITSTATUS (wait_status) != 0
+ : WTERMSIG (wait_status) != 0)
+ /* FIXME: It is not very clear what happened in sub-processes. */
+ if (task->error_so_far < task->fail_level)
+ {
+ task->error_so_far = task->fail_level;
+ task->error_at_step = request->sequence_array + (unsigned)request->sequence_length - 1;
+ }
}
- if (fclose (subtask->output.file) != 0)
- {
- recode_perror (NULL, "fclose (%s)", subtask->output.name ? subtask->output.name : "stdout");
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- }
-
- exit (task->error_so_far < task->fail_level ? EXIT_SUCCESS
- : EXIT_FAILURE);
- }
- else
- {
- /* The parent redirects the current input file to the pipe. */
- if (dup2 (pipe_pair[0], fileno (subtask->input.file)) < 0)
- {
- recode_perror (NULL, "dup2 ()");
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- SUBTASK_RETURN (subtask);
- }
- if (close (pipe_pair[0]) < 0)
- {
- recode_perror (NULL, "close ()");
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- SUBTASK_RETURN (subtask);
- }
- if (close (pipe_pair[1]) < 0)
- {
- recode_perror (NULL, "close ()");
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- SUBTASK_RETURN (subtask);
- }
+#if 0
+ if (interrupted) /* FIXME: interrupted is static in main.c */
+ /* FIXME: It is not very clear what happened in sub-processes. */
+ if (task->error_so_far < task->fail_level)
+ {
+ task->error_so_far = task->fail_level;
+ task->error_at_step = request->sequence_array + (unsigned)request->sequence_length - 1;
+ }
+#endif
}
}
-
- /* Perform the last recoding step and read its output. */
-
- if (!*subtask->output.name)
- subtask->output.file = stdout;
- else if (subtask->output.file = fopen (subtask->output.name, "w"),
- subtask->output.file == NULL)
- {
- recode_perror (NULL, "fopen (%s)", subtask->output.name);
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- SUBTASK_RETURN (subtask);
- }
-
- step = request->sequence_array + (unsigned)request->sequence_length - 1;
- subtask->step = step;
- (*step->transform_routine) (subtask);
-
- if (subtask->input.file && fclose (subtask->input.file) != 0)
- {
- recode_perror (NULL, "fclose (%s)", subtask->input.name ? subtask->input.name : "stdin");
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- SUBTASK_RETURN (subtask);
- }
-
- if (fclose (subtask->output.file) != 0)
- {
- recode_perror (NULL, "fclose (%s)", subtask->output.name ? subtask->output.name : "stdout");
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- SUBTASK_RETURN (subtask);
- }
-
- /* Wait on all children, mainly to avoid synchronisation problems on
- output file contents, but also to reduce the number of zombie
- processes in case the user recodes many files at once. */
-
- while (wait (&wait_status) > 0)
+ else
+#endif
{
- /* Diagnose and abort on any abnormally terminating child. */
-
- if (!(WIFEXITED (wait_status)
- || (WIFSIGNALED (wait_status)
- && WTERMSIG (wait_status) == SIGPIPE)))
- {
- recode_error (NULL, _("Child process wait status is 0x%0.2x"),
- wait_status);
- recode_if_nogo (RECODE_SYSTEM_ERROR, subtask);
- SUBTASK_RETURN (subtask);
- }
+ free (input.buffer);
+ free (output.buffer);
- /* Check for a nonzero exit from the terminating child. */
-
- if (WIFEXITED (wait_status)
- ? WEXITSTATUS (wait_status) != 0
- : WTERMSIG (wait_status) != 0)
- /* FIXME: It is not very clear what happened in sub-processes. */
- if (task->error_so_far < task->fail_level)
- {
- task->error_so_far = task->fail_level;
- task->error_at_step = step;
- }
+ task->output = subtask->output;
}
-#if 0
- if (interrupted)
- /* FIXME: It is not very clear what happened in sub-processes. */
- if (task->error_so_far < task->fail_level)
- {
- task->error_so_far = task->fail_level;
- task->error_at_step = step;
- }
-#endif
-
SUBTASK_RETURN (subtask);
}
-
-#endif /* HAVE_PIPE */
\f
/* Library interface. */
case RECODE_SEQUENCE_WITH_PIPE:
#if HAVE_PIPE
- success = perform_pipe_sequence (task);
+ success = perform_sequence (task, RECODE_SEQUENCE_WITH_PIPE);
break;
#else
/* Fall through on files if there are no pipes. */
projects / recode / commitdiff