pmap: new applet. +1k.

pmap is a tool used to look at processes' memory maps, normally found
in procps package. It provides more readable and easily sortable output
(one line per mapping) from  maps/smaps files in /proc/PID/.  This would
help in debugging memory usage issues, especially on devices where lots
of typing is not a viable option.

This patch does'n implement -d and -A command line options of GNU pmap,
since those are not that must have features and I was afraid of going
blind from looking at its code.

The implementation takes smaps scanning part out of procps_scan() function
and moves it into procps_read_smaps(), which does more detailed processing
of a single PID's smaps data.

Signed-off-by: Alexander Shishkin <virtuoso@slind.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 24 insertions, 7 deletions

diff --git a/include/libbb.h b/include/libbb.h
index 3fd754511..43e525cb9 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -1387,6 +1387,29 @@ enum { COMM_LEN = TASK_COMM_LEN };
 enum { COMM_LEN = 16 };
 # endif
 #endif
+
+struct smaprec {
+        unsigned long mapped_rw;
+        unsigned long mapped_ro;
+        unsigned long shared_clean;
+        unsigned long shared_dirty;
+        unsigned long private_clean;
+        unsigned long private_dirty;
+        unsigned long stack;
+        unsigned long smap_pss, smap_swap;
+        unsigned long smap_size;
+        unsigned long smap_start;
+        char smap_mode[5];
+        char *smap_name;
+};
+
+#if !ENABLE_PMAP
+#define procps_read_smaps(pid, total, cb, data) \
+        procps_read_smaps(pid, total)
+#endif
+int FAST_FUNC procps_read_smaps(pid_t pid, struct smaprec *total,
+                      void (*cb)(struct smaprec *, void *), void *data);
+
 typedef struct procps_status_t {
         DIR *dir;
         IF_FEATURE_SHOW_THREADS(DIR *task_dir;)
@@ -1415,13 +1438,7 @@ typedef struct procps_status_t {
 #endif
         unsigned tty_major,tty_minor;
 #if ENABLE_FEATURE_TOPMEM
-        unsigned long mapped_rw;
-        unsigned long mapped_ro;
-        unsigned long shared_clean;
-        unsigned long shared_dirty;
-        unsigned long private_clean;
-        unsigned long private_dirty;
-        unsigned long stack;
+        struct smaprec smaps;
 #endif
         char state[4];
         /* basename of executable in exec(2), read from /proc/N/stat