mx_util: Add mx_proc_pid_stat()

mx_util.c

@@ -842,6 +842,104 @@ int mx_strscan_ll(char **str, long long int *to)
     return res;
 }
 
+int mx_strscan_proc_pid_stat(char *str, struct proc_pid_stat *pps)
+{
+    size_t res = 0;
+    char *p;
+    char *s;
+
+    pps->comm = NULL;
+
+    s = str;
+
+    res += mx_strscan_ll(&s, &(pps->pid));
+
+    p = strrchr(s, ')');
+    if (!p)
+        return -(errno=EINVAL);
+
+    *p = 0;
+    s++;
+
+    pps->comm = mx_strdup_forever(s);
+    s = p + 2;
+
+    pps->state = *s;
+    res += !(*(s+1) == ' ');
+    s += 2;
+
+    res += mx_strscan_ll(&s, &(pps->ppid));
+    res += mx_strscan_ll(&s, &(pps->pgrp));
+    res += mx_strscan_ll(&s, &(pps->session));
+    res += mx_strscan_ll(&s, &(pps->tty_nr));
+    res += mx_strscan_ll(&s, &(pps->tpgid));
+    res += mx_strscan_ull(&s, &(pps->flags));
+    res += mx_strscan_ull(&s, &(pps->minflt));
+    res += mx_strscan_ull(&s, &(pps->cminflt));
+    res += mx_strscan_ull(&s, &(pps->majflt));
+    res += mx_strscan_ull(&s, &(pps->cmajflt));
+    res += mx_strscan_ull(&s, &(pps->utime));
+    res += mx_strscan_ull(&s, &(pps->stime));
+    res += mx_strscan_ll(&s, &(pps->cutime));
+    res += mx_strscan_ll(&s, &(pps->cstime));
+    res += mx_strscan_ll(&s, &(pps->priority));
+    res += mx_strscan_ll(&s, &(pps->nice));
+    res += mx_strscan_ll(&s, &(pps->num_threads));
+    res += mx_strscan_ll(&s, &(pps->itrealvalue));
+    res += mx_strscan_ull(&s, &(pps->starttime));
+    res += mx_strscan_ull(&s, &(pps->vsize));
+    res += mx_strscan_ll(&s, &(pps->rss));
+    res += mx_strscan_ull(&s, &(pps->rsslim));
+    res += mx_strscan_ull(&s, &(pps->startcode));
+    res += mx_strscan_ull(&s, &(pps->endcode));
+    res += mx_strscan_ull(&s, &(pps->startstack));
+    res += mx_strscan_ull(&s, &(pps->kstkesp));
+    res += mx_strscan_ull(&s, &(pps->kstkeip));
+    res += mx_strscan_ull(&s, &(pps->signal));
+    res += mx_strscan_ull(&s, &(pps->blocked));
+    res += mx_strscan_ull(&s, &(pps->sigignore));
+    res += mx_strscan_ull(&s, &(pps->sigcatch));
+    res += mx_strscan_ull(&s, &(pps->wchan));
+    res += mx_strscan_ull(&s, &(pps->nswap));
+    res += mx_strscan_ull(&s, &(pps->cnswap));
+    res += mx_strscan_ll(&s, &(pps->exit_signal));
+    res += mx_strscan_ll(&s, &(pps->processor));
+    res += mx_strscan_ull(&s, &(pps->rt_priority));
+    res += mx_strscan_ull(&s, &(pps->policy));
+    res += mx_strscan_ull(&s, &(pps->delayacct_blkio_ticks));
+    res += mx_strscan_ull(&s, &(pps->guest_time));
+    res += mx_strscan_ll(&s, &(pps->cguest_time));
+
+    if (res != 0)
+        return -(errno=EINVAL);
+
+    return 0;
+}
+
+int mx_proc_pid_stat(struct proc_pid_stat *pps, pid_t pid)
+{
+    _mx_cleanup_free_ char *fname = NULL;
+    _mx_cleanup_free_ char *line = NULL;
+    int res;
+
+    mx_asprintf_forever(&fname, "/proc/%d/stat", pid);
+
+    res = mx_read_first_line_from_file(fname, &line);
+    if (res < 0)
+        return res;
+
+    res = mx_strscan_proc_pid_stat(line, pps);
+    if (res < 0)
+        return res;
+
+    return 0;
+}
+
+void mx_proc_pid_stat_free(struct proc_pid_stat *pps)
+{
+    mx_free_null(pps->comm);
+}
+
 int mx_sleep(unsigned int seconds)
 {
     if (seconds)

mx_util.h

@@ -9,6 +9,53 @@
 
 #include "mx_log.h"
 
+struct proc_pid_stat {
+    long long int pid;     /* 1 */
+    char *comm;            /* 2 (comm) */
+    char state;            /* 3 "RSDZTW" */
+    long long int ppid;    /* 4 */
+    long long int pgrp;    /* 5 */
+    long long int session; /* 6 */
+    long long int tty_nr;  /* 7 */
+    long long int tpgid;   /* 8 */
+    unsigned long long int flags;   /*  9 */
+    unsigned long long int minflt;  /* 10 */
+    unsigned long long int cminflt; /* 11 */
+    unsigned long long int majflt;  /* 12 */
+    unsigned long long int cmajflt; /* 13 */
+    unsigned long long int utime;   /* 14 */
+    unsigned long long int stime;   /* 15 */
+    long long int cutime;   /* 16 */
+    long long int cstime;   /* 17 */
+    long long int priority; /* 18 */
+    long long int nice;     /* 19 */
+    long long int num_threads;          /* 20 */
+    long long int itrealvalue;          /* 21 */
+    unsigned long long int starttime;   /* 22 */
+    unsigned long long int vsize;       /* 23 */
+    long long int rss;                  /* 24 */
+    unsigned long long int rsslim;      /* 25 */
+    unsigned long long int startcode;   /* 26 */
+    unsigned long long int endcode;     /* 27 */
+    unsigned long long int startstack;  /* 28 */
+    unsigned long long int kstkesp;     /* 29 */
+    unsigned long long int kstkeip;     /* 30 */
+    unsigned long long int signal;      /* 31 */
+    unsigned long long int blocked;     /* 32 */
+    unsigned long long int sigignore;   /* 33 */
+    unsigned long long int sigcatch;    /* 34 */
+    unsigned long long int wchan;       /* 35 */
+    unsigned long long int nswap;       /* 36 */
+    unsigned long long int cnswap;      /* 37 */
+    long long int exit_signal;          /* 38 */
+    long long int processor;            /* 39 */
+    unsigned long long int rt_priority; /* 40 */
+    unsigned long long int policy;      /* 41 */
+    unsigned long long int delayacct_blkio_ticks; /* 42 */
+    unsigned long long int guest_time;  /* 43 */
+    long long int cguest_time;          /* 44 */
+};
+
 #ifdef MX_NDEBUG
 #   include <assert.h>
 #   define mx_assert_return_minus_errno(test, eno) \
@@ -119,6 +166,10 @@ int mx_read_first_line_from_file(char *fname, char **line);
 
 int mx_strscan_ull(char **str, unsigned long long int *to);
 int mx_strscan_ll(char **str, long long int *to);
+int mx_strscan_proc_pid_stat(char *str, struct proc_pid_stat *pps);
+
+int mx_proc_pid_stat(struct proc_pid_stat *pps, pid_t pid);
+void mx_proc_pid_stat_free(struct proc_pid_stat *pps);
 
 int mx_sleep(unsigned int seconds);
 int mx_sleep_nofail(unsigned int seconds);

test_mx_util.c

@@ -1,7 +1,11 @@
 
+#define _GNU_SOURCE
+
 #include <assert.h>
 #include <errno.h>
 #include <string.h>
+#include <sys/types.h>
+#include <unistd.h>
 
 #include "mx_util.h"
 
@@ -275,6 +279,7 @@ static void test_mx_strtobytes(void)
 static void test_mx_read_first_line_from_file(void)
 {
     char *str;
+    long long int l;
 
     assert(mx_read_first_line_from_file("/proc/sys/kernel/random/boot_id", &str) == 36);
     assert(str);
@@ -289,6 +294,7 @@ static void test_mx_read_first_line_from_file(void)
 
     assert(mx_read_first_line_from_file("/proc/self/stat", &str) > 0);
     assert(str);
+    mx_strtoll(str, &l);
     mx_free_null(str);
 }
 
@@ -298,6 +304,9 @@ static void test_mx_strscan(void)
     char *str;
     unsigned long long int ull;
     long long int ll;
+    _mx_cleanup_free_ char *line = NULL;
+    struct proc_pid_stat pps = {0};
+    struct proc_pid_stat pps2 = {0};
 
     assert(s = strdup("123 456 -789 246 abc"));
     str = s;
@@ -331,8 +340,23 @@ static void test_mx_strscan(void)
     assert(mx_streq(str, ""));
     assert(mx_streq(s, "123"));
 
+    assert(mx_read_first_line_from_file("/proc/self/stat", &line) > 0);
+    assert(mx_strscan_proc_pid_stat(line, &pps) == 0);
+    assert(pps.pid == getpid());
+    assert(pps.ppid == getppid());
+    assert(pps.state == 'R');
+    assert(mx_streq(pps.comm, program_invocation_short_name) || mx_streq(pps.comm, "memcheck-amd64-"));
+    mx_proc_pid_stat_free(&pps);
+
+    assert(mx_proc_pid_stat(&pps2, getpid()) == 0);
+    assert(pps2.pid == getpid());
+    assert(pps2.ppid == getppid());
+    assert(pps2.state == 'R');
+    assert(mx_streq(pps2.comm, program_invocation_short_name) || mx_streq(pps2.comm, "memcheck-amd64-"));
+    mx_proc_pid_stat_free(&pps2);
 }
 
+
 int main(int argc, char *argv[])
 {
     test_mx_strskipwhitespaces();