library: expanded to provide for the UID used at login

This patch represents the newlib implementation of Jan
Rybar's merge request referenced below. It essentially
moves that code out of the ps program and into our new
library where it's available via the <pids> interface.

Reference(s):
https://gitlab.com/procps-ng/procps/merge_requests/57
https://bugzilla.redhat.com/show_bug.cgi?id=1518986

Signed-off-by: Jim Warner <james.warner@comcast.net>

diff --git a/proc/pids.c b/proc/pids.c
index 5f9ea1e8709811cc1f30cb84d4ecdf2e4836c964..5928e4f6bed9cdf60c9c435dd8dd7c876ec9ac29 100644 (file)
--- a/proc/pids.c
+++ b/proc/pids.c
@@ -170,6 +170,7 @@ REG_set(ID_FGID,          u_int,   fgid)
 REG_set(ID_FGROUP,        str,     fgroup)
 REG_set(ID_FUID,          u_int,   fuid)
 REG_set(ID_FUSER,         str,     fuser)
+REG_set(ID_LOGIN,         s_int,   luid)
 REG_set(ID_PGRP,          s_int,   pgrp)
 REG_set(ID_PID,           s_int,   tid)
 REG_set(ID_PPID,          s_int,   ppid)
@@ -342,6 +343,7 @@ srtDECL(noop) {
 
 #define f_either   PROC_SPARE_1        // either status or stat (favor stat)
 #define f_grp      PROC_FILLGRP
+#define f_login    PROC_FILL_LUID
 #define f_lxc      PROC_FILL_LXC
 #define f_ns       PROC_FILLNS
 #define f_oom      PROC_FILLOOM
@@ -419,6 +421,7 @@ static struct {
     { RS(ID_FGROUP),         x_ogroup,   NULL,      QS(str),       0,        TS(str)     },
     { RS(ID_FUID),           f_status,   NULL,      QS(u_int),     0,        TS(u_int)   },
     { RS(ID_FUSER),          x_ouser,    NULL,      QS(str),       0,        TS(str)     }, // freefunc NULL w/ cached string
+    { RS(ID_LOGIN),          f_login,    NULL,      QS(s_int),     0,        TS(s_int)   },
     { RS(ID_PGRP),           f_stat,     NULL,      QS(s_int),     0,        TS(s_int)   },
     { RS(ID_PID),            0,          NULL,      QS(s_int),     0,        TS(s_int)   }, // oldflags: free w/ simple_nextpid
     { RS(ID_PPID),           f_either,   NULL,      QS(s_int),     0,        TS(s_int)   },

diff --git a/proc/pids.h b/proc/pids.h
index 96635b1d0f56cdf533878ddb90cd234178092b34..f6c158103c5fe49ed4306e00b82f4c5082272c62 100644 (file)
--- a/proc/pids.h
+++ b/proc/pids.h
@@ -59,6 +59,7 @@ enum pids_item {
     PIDS_ID_FGROUP,         //     str
     PIDS_ID_FUID,           //   u_int
     PIDS_ID_FUSER,          //     str
+    PIDS_ID_LOGIN,          //   s_int
     PIDS_ID_PGRP,           //   s_int
     PIDS_ID_PID,            //   s_int
     PIDS_ID_PPID,           //   s_int

diff --git a/proc/readproc.c b/proc/readproc.c
index 1fe7ce048a15229cb0254c968ca1f160f07dae69..77642f86a7c6dce6a664320796bf0cdd739247fb 100644 (file)
--- a/proc/readproc.c
+++ b/proc/readproc.c
@@ -877,6 +877,25 @@ static char *lxc_containers (const char *path) {
     }
     return lxc_none;
 }
+
+
+    // Provide the user id at login (or -1 if not available)
+static int login_uid (const char *path) {
+    char buf[PROCPATHLEN];
+    int fd, id, in;
+
+    id = -1;
+    snprintf(buf, sizeof(buf), "%s/loginuid", path);
+    if ((fd = open(buf, O_RDONLY, 0)) != -1) {
+        in = read(fd, buf, sizeof(buf) - 1);
+        close(fd);
+        if (in > 0) {
+            buf[in] = '\0';
+            id = atoi(buf);
+        }
+    }
+    return id;
+}
 ///////////////////////////////////////////////////////////////////////
 
 
@@ -998,6 +1017,9 @@ static proc_t* simple_readproc(PROCTAB *restrict const PT, proc_t *restrict cons
     if (flags & PROC_FILL_LXC)                  // value the lxc name
         p->lxcname = lxc_containers(path);
 
+    if (flags & PROC_FILL_LUID)                 // value the login user id
+        p->luid = login_uid(path);
+
     if (rc == 0) return p;
     errno = ENOMEM;
 next_proc:
@@ -1132,6 +1154,9 @@ static proc_t* simple_readtask(PROCTAB *restrict const PT, const proc_t *restric
     if (flags & PROC_FILL_LXC)
         t->lxcname = lxc_containers(path);
 
+    if (flags & PROC_FILL_LUID)
+        t->luid = login_uid(path);
+
     if (rc == 0) return t;
     errno = ENOMEM;
 next_task:

diff --git a/proc/readproc.h b/proc/readproc.h
index 7fa09e848bb0efb57e98366fb395a7b57873b878..a477570ca40e5a1aafe95c9d7b0672326f7c53dc 100644 (file)
--- a/proc/readproc.h
+++ b/proc/readproc.h
@@ -165,6 +165,8 @@ typedef struct proc_t {
         *sd_uunit;      // n/a             systemd user unit id
     char
         *lxcname;       // n/a             lxc container name
+    int
+        luid;           // loginuid        user id at login
 } proc_t;
 
 // PROCTAB: data structure holding the persistent information readproc needs
@@ -223,6 +225,7 @@ typedef struct PROCTAB {
 #define PROC_FILLNS          0x8000 // fill in proc_t namespace information
 #define PROC_FILLSYSTEMD    0x80000 // fill in proc_t systemd information
 #define PROC_FILL_LXC      0x800000 // fill in proc_t lxcname, if possible
+#define PROC_FILL_LUID     0x400000 // fill in proc_t luid (login user id)
 
 #define PROC_LOOSE_TASKS     0x2000 // treat threads as if they were processes