summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJeremie Koenig <jk@jk.fr.eu.org>2010-08-23 16:46:04 +0000
committerJeremie Koenig <jk@jk.fr.eu.org>2010-08-30 14:31:32 +0200
commit7550343b09a94dc1c659ad74dc75b3b77e7ab0bc (patch)
treeb16bb4c7c8d266297ecf0c38e9bc9c055d8b91a2
parentf522af65aa004fea09705c74115836c6acd1cddb (diff)
Cleanup pass on process.c
* process.c: Reorder some of the code. Improve comments. Jiffies and clock tick are the same thing, right? Replace the stat mode and cleanup hacks by more straightforward solutions.
-rw-r--r--process.c122
1 files changed, 79 insertions, 43 deletions
diff --git a/process.c b/process.c
index 61688f7..1f9d578 100644
--- a/process.c
+++ b/process.c
@@ -9,22 +9,20 @@
#include "procfs_dir.h"
#include "process.h"
#include "main.h"
-
-/* Implementations for the process_file_desc.get_contents callback. */
-static ssize_t
-process_file_gc_cmdline (struct proc_stat *ps, char **contents)
-{
- *contents = proc_stat_args(ps);
- return proc_stat_args_len(ps);
-}
+/* This module implements the process directories and the files they
+ contain. A libps proc_stat structure is created for each process
+ node, and is used by the individual file content generators as a
+ source of information. Each possible file (cmdline, environ, ...) is
+ decribed in a process_file_desc structure, which specifies which bits
+ of information (ie. libps flags) it needs, and what function should
+ be used to generate the file's contents.
-static ssize_t
-process_file_gc_environ (struct proc_stat *ps, char **contents)
-{
- *contents = proc_stat_env(ps);
- return proc_stat_env_len(ps);
-}
+ The content generators are defined first, followed by glue logic and
+ entry table. */
+
+
+/* Helper functions */
static char state_char (struct proc_stat *ps)
{
@@ -58,17 +56,26 @@ static const char *state_string (struct proc_stat *ps)
return "? (unknown)";
}
-static long int sc_tv (time_value_t tv)
+static long long int timeval_jiffies (time_value_t tv)
{
- double usecs = ((double) tv.seconds) * 1000000 + tv.microseconds;
- return usecs * opt_clk_tck / 1000000;
+ double secs = tv.seconds + tv.microseconds / 1000000.;
+ return secs * opt_clk_tck;
}
-static long long int jiff_tv (time_value_t tv)
+/* Actual content generators */
+
+static ssize_t
+process_file_gc_cmdline (struct proc_stat *ps, char **contents)
{
- double usecs = ((double) tv.seconds) * 1000000 + tv.microseconds;
- /* Let's say a jiffy is 1/100 of a second.. */
- return usecs * 100 / 1000000;
+ *contents = proc_stat_args(ps);
+ return proc_stat_args_len(ps);
+}
+
+static ssize_t
+process_file_gc_environ (struct proc_stat *ps, char **contents)
+{
+ *contents = proc_stat_env(ps);
+ return proc_stat_env_len(ps);
}
static ssize_t
@@ -105,17 +112,18 @@ process_file_gc_stat (struct proc_stat *ps, char **contents)
0, 0, /* no such thing as a major:minor for ctty */
0, /* no such thing as CLONE_* flags on Hurd */
0L, 0L, 0L, 0L, /* TASK_EVENTS_INFO is unavailable on GNU Mach */
- sc_tv (thbi->user_time), sc_tv (thbi->system_time),
+ (long unsigned) timeval_jiffies (thbi->user_time),
+ (long unsigned) timeval_jiffies (thbi->system_time),
0L, 0L, /* cumulative time for children */
MACH_PRIORITY_TO_NICE(thbi->base_priority) + 20,
MACH_PRIORITY_TO_NICE(thbi->base_priority),
pi->nthreads, 0L,
- jiff_tv (thbi->creation_time), /* FIXME: ... since boot */
- (long unsigned int) tbi->virtual_size,
- (long unsigned int) tbi->resident_size / PAGE_SIZE, 0L,
+ timeval_jiffies (thbi->creation_time), /* FIXME: ... since boot */
+ (long unsigned) tbi->virtual_size,
+ (long unsigned) tbi->resident_size / PAGE_SIZE, 0L,
0L, 0L, 0L, 0L, 0L,
0L, 0L, 0L, 0L,
- (long unsigned int) proc_stat_thread_rpc (ps), /* close enough */
+ (long unsigned) proc_stat_thread_rpc (ps), /* close enough */
0L, 0L,
0,
0,
@@ -127,6 +135,7 @@ static ssize_t
process_file_gc_statm (struct proc_stat *ps, char **contents)
{
task_basic_info_t tbi = proc_stat_task_basic_info (ps);
+
return asprintf (contents,
"%lu %lu 0 0 0 0 0\n",
tbi->virtual_size / sysconf(_SC_PAGE_SIZE),
@@ -137,6 +146,7 @@ static ssize_t
process_file_gc_status (struct proc_stat *ps, char **contents)
{
task_basic_info_t tbi = proc_stat_task_basic_info (ps);
+
return asprintf (contents,
"Name:\t%s\n"
"State:\t%s\n"
@@ -165,59 +175,70 @@ process_file_gc_status (struct proc_stat *ps, char **contents)
proc_stat_num_threads (ps));
}
+
+/* Implementation of the file nodes. */
-/* Describes a file in a process directory. This is used as an "entry hook"
- * for our procfs_dir entry table, passed to process_file_make_node. */
+/* Describes a file in the process directories. This structure is
+ filled in as an "entry hook" in our procfs_dir entry table and is
+ passed to the process_file_make_node function defined below. */
struct process_file_desc
{
/* The proc_stat information required to get the contents of this file. */
ps_flags_t needs;
- /* Once we have acquired the necessary information, there can be only
- memory allocation errors, hence this simplified signature. */
+ /* Content generator to use for this file. Once we have acquired the
+ necessary information, there can be only memory allocation errors,
+ hence this simplified signature. */
ssize_t (*get_contents) (struct proc_stat *ps, char **contents);
- /* The cmdline and environ contents don't need any cleaning since they are
- part of a proc_stat structure. */
+ /* The cmdline and environ contents don't need any cleaning since they
+ point directly into the proc_stat structure. */
int no_cleanup;
/* If specified, the file mode to be set with procfs_node_chmod(). */
mode_t mode;
};
-/* Information associated to an actual file node. */
struct process_file_node
{
const struct process_file_desc *desc;
struct proc_stat *ps;
};
+/* FIXME: lock the parent! */
static error_t
process_file_get_contents (void *hook, char **contents, ssize_t *contents_len)
{
struct process_file_node *file = hook;
error_t err;
+ /* Fetch the required information. */
err = proc_stat_set_flags (file->ps, file->desc->needs);
if (err)
return EIO;
if ((proc_stat_flags (file->ps) & file->desc->needs) != file->desc->needs)
return EIO;
+ /* Call the actual content generator (see the definitions below). */
*contents_len = file->desc->get_contents (file->ps, contents);
return 0;
}
+static void
+process_file_cleanup_contents (void *hook, char *contents, ssize_t len)
+{
+ struct process_file_node *file = hook;
+
+ if (! file->desc->no_cleanup)
+ free (contents);
+}
+
static struct node *
process_file_make_node (void *dir_hook, const void *entry_hook)
{
static const struct procfs_node_ops ops = {
.get_contents = process_file_get_contents,
- .cleanup_contents = procfs_cleanup_contents_with_free,
- .cleanup = free,
- };
- static const struct procfs_node_ops ops_no_cleanup = {
- .get_contents = process_file_get_contents,
+ .cleanup_contents = process_file_cleanup_contents,
.cleanup = free,
};
struct process_file_node *f;
@@ -230,7 +251,7 @@ process_file_make_node (void *dir_hook, const void *entry_hook)
f->desc = entry_hook;
f->ps = dir_hook;
- np = procfs_make_node (f->desc->no_cleanup ? &ops_no_cleanup : &ops, f);
+ np = procfs_make_node (&ops, f);
if (! np)
return NULL;
@@ -241,6 +262,18 @@ process_file_make_node (void *dir_hook, const void *entry_hook)
return np;
}
+/* Stat needs its own constructor in oreder to set its mode according to
+ the --stat-mode command-line option. */
+static struct node *
+process_stat_make_node (void *dir_hook, const void *entry_hook)
+{
+ struct node *np = process_file_make_node (dir_hook, entry_hook);
+ if (np) procfs_node_chmod (np, opt_stat_mode);
+ return np;
+}
+
+
+/* Implementation of the process directory per se. */
static struct procfs_dir_entry entries[] = {
{
@@ -261,22 +294,22 @@ static struct procfs_dir_entry entries[] = {
},
},
{
- /* Beware of the hack below, which requires this to be entries[2]. */
.name = "stat",
.hook = & (struct process_file_desc) {
.get_contents = process_file_gc_stat,
.needs = PSTAT_PID | PSTAT_ARGS | PSTAT_STATE | PSTAT_PROC_INFO
| PSTAT_TASK | PSTAT_TASK_BASIC | PSTAT_THREAD_BASIC
| PSTAT_THREAD_WAIT,
- .mode = 0400,
},
+ .ops = {
+ .make_node = process_stat_make_node,
+ }
},
{
.name = "statm",
.hook = & (struct process_file_desc) {
.get_contents = process_file_gc_statm,
.needs = PSTAT_TASK_BASIC,
- .mode = 0444,
},
},
{
@@ -285,7 +318,6 @@ static struct procfs_dir_entry entries[] = {
.get_contents = process_file_gc_status,
.needs = PSTAT_PID | PSTAT_ARGS | PSTAT_STATE | PSTAT_PROC_INFO
| PSTAT_TASK_BASIC | PSTAT_OWNER_UID | PSTAT_NUM_THREADS,
- .mode = 0444,
},
},
{}
@@ -319,6 +351,10 @@ process_lookup_pid (struct ps_context *pc, pid_t pid, struct node **np)
accessed in a more robust and straightforward way. */
((struct process_file_desc *) entries[2].hook)->mode = opt_stat_mode;
+ /* FIXME: have a separate proc_desc structure for each file, so this can be
+ accessed in a more robust and straightforward way. */
+ ((struct process_file_desc *) entries[2].hook)->mode = opt_stat_mode;
+
*np = procfs_dir_make_node (&dir_ops, ps);
if (! *np)
return ENOMEM;