From e33f5bed237e860dc16381ae95cdd68f7fc341e7 Mon Sep 17 00:00:00 2001
From: sin <sin@2f30.org>
Date: Fri, 16 Aug 2013 16:36:52 +0100
Subject: [PATCH] Add parsestatus()

---
 proc.h      |  8 ++++++
 ps.c        | 13 +++++----
 util/proc.c | 81 +++++++++++++++++++++--------------------------------
 3 files changed, 47 insertions(+), 55 deletions(-)

diff --git a/proc.h b/proc.h
index 3cc7d29..22caa11 100644
--- a/proc.h
+++ b/proc.h
@@ -27,8 +27,16 @@ struct procstat {
 	long rsslim;
 };
 
+struct procstatus {
+	uid_t uid;
+	uid_t euid;
+	gid_t gid;
+	gid_t egid;
+};
+
 int parsecmdline(pid_t pid, char *buf, size_t siz);
 int parsestat(pid_t pid, struct procstat *ps);
+int parsestatus(pid_t pid, struct procstatus *pstatus);
 int proceuid(pid_t pid, uid_t *euid);
 int procuid(pid_t pid, uid_t *euid);
 int validps(const char *path);
diff --git a/ps.c b/ps.c
index f51df0a..ef0935e 100644
--- a/ps.c
+++ b/ps.c
@@ -64,11 +64,12 @@ usage(void)
 static void
 psout(struct procstat *ps)
 {
+	struct procstatus pstatus;
 	char cmdline[BUFSIZ], *cmd;
 	char stimestr[6];
 	char *ttystr, *myttystr;
 	int tty_maj, tty_min;
-	uid_t myeuid, peuid, puid;
+	uid_t myeuid;
 	unsigned sutime;
 	time_t start;
 	struct sysinfo info;
@@ -91,6 +92,8 @@ psout(struct procstat *ps)
 		}
 	}
 
+	parsestatus(ps->pid, &pstatus);
+
 	/* This is the default case, only print processes that have
 	 * the same controlling terminal as the invoker and the same
 	 * euid as the current user */
@@ -107,9 +110,8 @@ psout(struct procstat *ps)
 			ttystr[0] = '?';
 			ttystr[1] = '\0';
 		}
-		proceuid(ps->pid, &peuid);
 		myeuid = geteuid();
-		if (myeuid != peuid) {
+		if (myeuid != pstatus.euid) {
 			free(ttystr);
 			return;
 		}
@@ -122,11 +124,10 @@ psout(struct procstat *ps)
 		       sutime / 3600, (sutime % 3600) / 60, sutime % 60,
 		       ps->comm);
 	} else {
-		procuid(ps->pid, &puid);
 		errno = 0;
-		pw = getpwuid(puid);
+		pw = getpwuid(pstatus.uid);
 		if (errno || !pw)
-			eprintf("getpwuid %d:", puid);
+			eprintf("getpwuid %d:", pstatus.uid);
 
 		if (sysinfo(&info) < 0)
 			eprintf("sysinfo:");
diff --git a/util/proc.c b/util/proc.c
index 5831019..7924aab 100644
--- a/util/proc.c
+++ b/util/proc.c
@@ -10,55 +10,6 @@
 #include "../proc.h"
 #include "../util.h"
 
-/* TODO: Unify proc{euid,uid}() into parsestatus() */
-int
-proceuid(pid_t pid, uid_t *euid)
-{
-	FILE *fp;
-	char buf[BUFSIZ], *p;
-	char path[PATH_MAX];
-	uid_t procuid, proceuid;
-
-	snprintf(path, sizeof(path), "/proc/%d/status", pid);
-	if (!(fp = fopen(path, "r")))
-		eprintf("%s fopen:", path);
-	while (fgets(buf, sizeof(buf), fp)) {
-		if (!strncmp(buf, "Uid:", 4)) {
-			p = buf + strlen("Uid:");
-			sscanf(p, "%u %u", &procuid, &proceuid);
-			*euid = proceuid;
-			fclose(fp);
-			return 0;
-		}
-	}
-	fclose(fp);
-	return -1;
-}
-
-int
-procuid(pid_t pid, uid_t *uid)
-{
-	FILE *fp;
-	char buf[BUFSIZ], *p;
-	char path[PATH_MAX];
-	uid_t procuid;
-
-	snprintf(path, sizeof(path), "/proc/%d/status", pid);
-	if (!(fp = fopen(path, "r")))
-		eprintf("%s fopen:", path);
-	while (fgets(buf, sizeof(buf), fp)) {
-		if (!strncmp(buf, "Uid:", 4)) {
-			p = buf + strlen("Uid:");
-			sscanf(p, "%u", &procuid);
-			*uid = procuid;
-			fclose(fp);
-			return 0;
-		}
-	}
-	fclose(fp);
-	return -1;
-}
-
 int
 parsecmdline(pid_t pid, char *buf, size_t siz)
 {
@@ -111,6 +62,38 @@ parsestat(pid_t pid, struct procstat *ps)
 	return 0;
 }
 
+int
+parsestatus(pid_t pid, struct procstatus *pstatus)
+{
+	char path[PATH_MAX];
+	char buf[BUFSIZ], *off;
+	int fd;
+	ssize_t n;
+
+	snprintf(path, sizeof(path), "/proc/%d/status", pid);
+	fd = open(path, O_RDONLY);
+	if (fd < 0)
+		eprintf("open %s:", path);
+	n = read(fd, buf, sizeof(buf) - 1);
+	if (n < 0)
+		eprintf("%s: read error:", path);
+	if (!n) {
+		close(fd);
+		return -1;
+	}
+	buf[n] = '\0';
+	close(fd);
+	off = strstr(buf, "Uid:");
+	if (!off)
+		return -1;
+	sscanf(off, "Uid: %u %u", &pstatus->uid, &pstatus->euid);
+	off = strstr(buf, "Gid:");
+	if (!off)
+		return -1;
+	sscanf(off, "Gid: %u %u", &pstatus->gid, &pstatus->egid);
+	return 0;
+}
+
 int
 validps(const char *path)
 {