ipcs: read shared memory values from /proc

[kzak@redhat.com: - move to ipcutils.{c,h},
                  - fix datatypes to be arch independent]

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
Signed-off-by: Karel Zak <kzak@redhat.com>

3 files changed, 205 insertions, 39 deletions

diff --git a/sys-utils/ipcs.c b/sys-utils/ipcs.c
index b904bb326..496fc334c 100644
--- a/sys-utils/ipcs.c
+++ b/sys-utils/ipcs.c
@@ -25,14 +25,14 @@
 
 #include "ipcutils.h"
 
-
 #define LIMITS 1
 #define STATUS 2
 #define CREATOR 3
 #define TIME 4
 #define PID 5
 
-void do_shm (char format);
+static void do_shm (char format);
+
 void do_sem (char format);
 void do_msg (char format);
 void print_shm (int id);
@@ -190,14 +190,13 @@ static void print_perms (int id, struct ipc_perm *ipcp)
 		printf(" %-10u\n", ipcp->gid);
 }
 
-void do_shm (char format)
+static void do_shm (char format)
 {
-	int maxid, shmid, id;
-	struct shmid_ds shmseg;
+	int maxid;
 	struct shm_info shm_info;
-	struct ipc_perm *ipcp = &shmseg.shm_perm;
 	struct passwd *pw;
 	struct ipc_limits lim;
+	struct shm_data *shmds, *shmdsp;
 
 	maxid = shmctl (0, SHM_INFO, (struct shmid_ds *) (void *) &shm_info);
 	if (maxid < 0) {
@@ -269,60 +268,56 @@ void do_shm (char format)
 		break;
 	}
 
-	for (id = 0; id <= maxid; id++) {
-		shmid = shmctl (id, SHM_STAT, &shmseg);
-		if (shmid < 0)
-			continue;
+	if (ipc_shm_get_info(maxid, -1, &shmds) < 1)
+		return;
+	shmdsp = shmds;
+
+	for (shmdsp = shmds; shmdsp->next != NULL; shmdsp = shmdsp->next) {
 		if (format == CREATOR)  {
-			print_perms (shmid, ipcp);
+			ipc_print_perms(stdout, &shmdsp->shm_perm);
 			continue;
 		}
-		pw = getpwuid(ipcp->uid);
+		pw = getpwuid(shmdsp->shm_perm.uid);
 		switch (format) {
 		case TIME:
 			if (pw)
-				printf ("%-10d %-10.10s", shmid, pw->pw_name);
+				printf ("%-10d %-10.10s", shmdsp->shm_perm.id, pw->pw_name);
 			else
-				printf ("%-10d %-10u", shmid, ipcp->uid);
+				printf ("%-10d %-10u", shmdsp->shm_perm.id, shmdsp->shm_perm.uid);
 			/* ctime uses static buffer: use separate calls */
-			printf(" %-20.16s", shmseg.shm_atime
-			       ? ctime(&shmseg.shm_atime) + 4 : _("Not set"));
-			printf(" %-20.16s", shmseg.shm_dtime
-			       ? ctime(&shmseg.shm_dtime) + 4 : _("Not set"));
-			printf(" %-20.16s\n", shmseg.shm_ctime
-			       ? ctime(&shmseg.shm_ctime) + 4 : _("Not set"));
+			printf(" %-20.16s", shmdsp->shm_atim
+			       ? ctime(&shmdsp->shm_atim) + 4 : _("Not set"));
+			printf(" %-20.16s", shmdsp->shm_dtim
+			       ? ctime(&shmdsp->shm_dtim) + 4 : _("Not set"));
+			printf(" %-20.16s\n", shmdsp->shm_ctim
+			       ? ctime(&shmdsp->shm_ctim) + 4 : _("Not set"));
 			break;
 		case PID:
 			if (pw)
-				printf ("%-10d %-10.10s", shmid, pw->pw_name);
+				printf ("%-10d %-10.10s", shmdsp->shm_perm.id, pw->pw_name);
 			else
-				printf ("%-10d %-10u", shmid, ipcp->uid);
-			printf (" %-10d %-10d\n",
-				shmseg.shm_cpid, shmseg.shm_lpid);
+				printf ("%-10d %-10u", shmdsp->shm_perm.id, shmdsp->shm_perm.uid);
+			printf (" %-10u %-10u\n",
+				shmdsp->shm_cprid, shmdsp->shm_lprid);
 			break;
 
 		default:
-			printf("0x%08x ",ipcp->KEY );
+			printf("0x%08x ", shmdsp->shm_perm.key);
 			if (pw)
-				printf ("%-10d %-10.10s", shmid, pw->pw_name);
+				printf ("%-10d %-10.10s", shmdsp->shm_perm.id, pw->pw_name);
 			else
-				printf ("%-10d %-10u", shmid, ipcp->uid);
+				printf ("%-10d %-10u", shmdsp->shm_perm.id, shmdsp->shm_perm.uid);
 			printf (" %-10o %-10lu %-10ld %-6s %-6s\n",
-				ipcp->mode & 0777,
-				/*
-				 * earlier: int, Austin has size_t
-				 */
-				(unsigned long) shmseg.shm_segsz,
-				/*
-				 * glibc-2.1.3 and earlier has unsigned short;
-				 * Austin has shmatt_t
-				 */
-				(long) shmseg.shm_nattch,
-				ipcp->mode & SHM_DEST ? _("dest") : " ",
-				ipcp->mode & SHM_LOCKED ? _("locked") : " ");
+				shmdsp->shm_perm.mode & 0777,
+				shmdsp->shm_segsz,
+				shmdsp->shm_nattch,
+				shmdsp->shm_perm.mode & SHM_DEST ? _("dest") : " ",
+				shmdsp->shm_perm.mode & SHM_LOCKED ? _("locked") : " ");
 			break;
 		}
 	}
+
+	ipc_shm_free_info(shmds);
 	return;
 }
 
diff --git a/sys-utils/ipcutils.c b/sys-utils/ipcutils.c
index 041f35062..c266ad868 100644
--- a/sys-utils/ipcutils.c
+++ b/sys-utils/ipcutils.c
@@ -1,5 +1,8 @@
 
+#include <inttypes.h>
+
 #include "c.h"
+#include "xalloc.h"
 #include "path.h"
 #include "pathnames.h"
 #include "ipcutils.h"
@@ -87,3 +90,138 @@ int ipc_shm_get_limits(struct ipc_limits *lim)
 
 	return 0;
 }
+
+int ipc_shm_get_info(int maxid, int id, struct shm_data **shmds)
+{
+	FILE *f;
+	int i;
+	struct shm_data *p;
+
+	p = *shmds = xmalloc(sizeof(struct shm_data));
+	p->next = NULL;
+
+	f = path_fopen("r", 0, _PATH_PROC_SYSV_SHM);
+	if (!f)
+		goto fallback;
+
+	while (fgetc(f) != '\n');		/* skip header */
+
+	for (i = 0; !feof(f); i++) {
+		if (fscanf(f,
+			  "%d %d  %o %"SCNu64 " %u %u  "
+			  "%"SCNu64 " %u %u %u %u %"SCNu64 " %"SCNu64 " %"SCNu64
+			  " %"SCNu64 " %"SCNu64 "\n",
+			   &p->shm_perm.key,
+			   &p->shm_perm.id,
+			   &p->shm_perm.mode,
+			   &p->shm_segsz,
+			   &p->shm_cprid,
+			   &p->shm_lprid,
+			   &p->shm_nattch,
+			   &p->shm_perm.uid,
+			   &p->shm_perm.gid,
+			   &p->shm_perm.cuid,
+			   &p->shm_perm.cgid,
+			   &p->shm_atim,
+			   &p->shm_dtim,
+			   &p->shm_ctim,
+			   &p->shm_rss,
+			   &p->shm_swp) != 16)
+			continue;
+
+		if (id < 0) {
+			p->next = xmalloc(sizeof(struct shm_data));
+			p = p->next;
+			p->next = NULL;
+		}
+	}
+
+	if (i == 0)
+		free(*shmds);
+	fclose(f);
+	return i;
+
+	/* Fallback; /proc or /sys file(s) missing. */
+fallback:
+	i = id < 0 ? 0 : id;
+
+	while (i <= maxid) {
+		int shmid;
+		struct shmid_ds shmseg;
+		struct ipc_perm *ipcp = &shmseg.shm_perm;
+
+		shmid = shmctl(i, SHM_STAT, &shmseg);
+		if (shmid < 0) {
+			if (-1 < id) {
+				free(*shmds);
+				return 0;
+			}
+			i++;
+			continue;
+		}
+
+		p->shm_perm.key = ipcp->KEY;
+		p->shm_perm.id = shmid;
+		p->shm_perm.mode = ipcp->mode;
+		p->shm_segsz = shmseg.shm_segsz;
+		p->shm_cprid = shmseg.shm_cpid;
+		p->shm_lprid = shmseg.shm_lpid;
+		p->shm_nattch = shmseg.shm_nattch;
+		p->shm_perm.uid = ipcp->uid;
+		p->shm_perm.gid = ipcp->gid;
+		p->shm_perm.cuid = ipcp->cuid;
+		p->shm_perm.cgid = ipcp->cuid;
+		p->shm_atim = shmseg.shm_atime;
+		p->shm_dtim = shmseg.shm_dtime;
+		p->shm_ctim = shmseg.shm_ctime;
+		p->shm_rss = 0xdead;
+		p->shm_swp = 0xdead;
+
+		if (id < 0) {
+			p->next = xmalloc(sizeof(struct shm_data));
+			p = p->next;
+			p->next = NULL;
+			i++;
+		} else
+			return 1;
+	}
+
+	return i;
+}
+
+void ipc_shm_free_info(struct shm_data *shmds)
+{
+	while (shmds) {
+		struct shm_data *next = shmds->next;
+		free(shmds);
+		shmds = next;
+	}
+}
+
+void ipc_print_perms(FILE *f, struct ipc_stat *is)
+{
+	struct passwd *pw;
+	struct group *gr;
+
+	fprintf(f, "%-10d %-10o", is->id, is->mode & 0777);
+
+	if ((pw = getpwuid(is->cuid)))
+		fprintf(f, " %-10s", pw->pw_name);
+	else
+		fprintf(f, " %-10u", is->cuid);
+
+	if ((gr = getgrgid(is->cgid)))
+		fprintf(f, " %-10s", gr->gr_name);
+	else
+		fprintf(f, " %-10u", is->cgid);
+
+	if ((pw = getpwuid(is->uid)))
+		fprintf(f, " %-10s", pw->pw_name);
+	else
+		fprintf(f, " %-10u", is->uid);
+
+	if ((gr = getgrgid(is->gid)))
+		fprintf(f, " %-10s\n", gr->gr_name);
+	else
+		fprintf(f, " %-10u\n", is->gid);
+}
diff --git a/sys-utils/ipcutils.h b/sys-utils/ipcutils.h
index ef539ee6c..8e2bfddfb 100644
--- a/sys-utils/ipcutils.h
+++ b/sys-utils/ipcutils.h
@@ -99,4 +99,37 @@ extern int ipc_msg_get_limits(struct ipc_limits *lim);
 extern int ipc_sem_get_limits(struct ipc_limits *lim);
 extern int ipc_shm_get_limits(struct ipc_limits *lim);
 
+struct ipc_stat {
+	int		id;
+	key_t		key;
+	uid_t		uid;    /* current uid */
+	gid_t		gid;    /* current gid */
+	uid_t		cuid;    /* creator uid */
+	gid_t		cgid;    /* creator gid */
+	unsigned int	mode;
+};
+
+extern void ipc_print_perms(FILE *f, struct ipc_stat *is);
+
+/* See 'struct shmid_kernel' in kernel sources
+ */
+struct shm_data {
+	struct ipc_stat	shm_perm;
+
+	uint64_t	shm_nattch;
+	uint64_t	shm_segsz;
+	time_t		shm_atim;
+	time_t		shm_dtim;
+	time_t		shm_ctim;
+	pid_t		shm_cprid;
+	pid_t		shm_lprid;
+	uint64_t	shm_rss;
+	uint64_t	shm_swp;
+
+	struct shm_data  *next;
+};
+
+extern int ipc_shm_get_info(int maxid, int id, struct shm_data **shmds);
+extern void ipc_shm_free_info(struct shm_data *shmds);
+
 #endif /* UTIL_LINUX_IPCUTILS_H */