Make 64-bit procstat output ELF auxiliary vectors for 32-bit processes.

Reviewed by:	kib
MFC after:	1 week

1 files changed, 87 insertions, 16 deletions

diff --git a/usr.bin/procstat/procstat_auxv.c b/usr.bin/procstat/procstat_auxv.c
index 543738c..73a85cd 100644
--- a/usr.bin/procstat/procstat_auxv.c
+++ b/usr.bin/procstat/procstat_auxv.c
@@ -43,39 +43,110 @@
 
 #include "procstat.h"
 
-static Elf_Auxinfo auxv[256];
+#define PROC_AUXV_MAX	256
+
+static Elf_Auxinfo auxv[PROC_AUXV_MAX];
 static char prefix[256];
 
+#if __ELF_WORD_SIZE == 64
+static Elf32_Auxinfo auxv32[PROC_AUXV_MAX];
+
+static const char *elf32_sv_names[] = {
+	"Linux ELF32",
+	"FreeBSD ELF32",
+};
+
+static int
+is_elf32(pid_t pid)
+{
+	int error, name[4];
+	size_t len, i;
+	static char sv_name[256];
+
+	name[0] = CTL_KERN;
+	name[1] = KERN_PROC;
+	name[2] = KERN_PROC_SV_NAME;
+	name[3] = pid;
+	len = sizeof(sv_name);
+	error = sysctl(name, 4, sv_name, &len, NULL, 0);
+	if (error != 0 || len == 0)
+		return (0);
+	for (i = 0; i < sizeof(elf32_sv_names) / sizeof(*elf32_sv_names); i++) {
+		if (strncmp(sv_name, elf32_sv_names[i], sizeof(sv_name)) == 0)
+			return (1);
+	}
+	return (0);
+}
+
+static size_t
+retrieve_auxv32(pid_t pid)
+{
+	int error, name[4];
+	size_t len, i;
+	void *ptr;
+
+	name[0] = CTL_KERN;
+	name[1] = KERN_PROC;
+	name[2] = KERN_PROC_AUXV;
+	name[3] = pid;
+	len = sizeof(auxv32);
+	error = sysctl(name, 4, auxv32, &len, NULL, 0);
+	if (error < 0 && errno != ESRCH && errno != EPERM) {
+		warn("sysctl: kern.proc.auxv: %d: %d", pid, errno);
+		return (0);
+	}
+	for (i = 0; i < len; i++) {
+		/*
+		 * XXX: We expect that values for a_type on a 32-bit platform
+		 * are directly mapped to those on 64-bit one, which is not
+		 * necessarily true.
+		 */
+		auxv[i].a_type = auxv32[i].a_type;
+		ptr = &auxv32[i].a_un;
+		auxv[i].a_un.a_val = *((uint32_t *)ptr);
+	}
+	return (len);
+}
+#endif /* __ELF_WORD_SIZE == 64 */
+
 #define	PRINT(name, spec, val)		\
 	printf("%s %-16s " #spec "\n", prefix, #name, (val))
 #define	PRINT_UNKNOWN(type, val)	\
 	printf("%s %16ld %#lx\n", prefix, (long)type, (u_long)(val))
 
-void
-procstat_auxv(struct kinfo_proc *kipp)
+static size_t
+retrieve_auxv(pid_t pid)
 {
 	int error, name[4];
-	size_t len, i;
-
-	if (!hflag)
-		printf("%5s %-16s %-16s %-16s\n", "PID", "COMM", "AUXV", "VALUE");
+	size_t len;
 
+#if __ELF_WORD_SIZE == 64
+	if (is_elf32(pid))
+		return (retrieve_auxv32(pid));
+#endif
 	name[0] = CTL_KERN;
 	name[1] = KERN_PROC;
 	name[2] = KERN_PROC_AUXV;
-	name[3] = kipp->ki_pid;
-	len = sizeof(auxv) * sizeof(*auxv);
+	name[3] = pid;
+	len = sizeof(auxv);
 	error = sysctl(name, 4, auxv, &len, NULL, 0);
 	if (error < 0 && errno != ESRCH && errno != EPERM) {
-		warn("sysctl: kern.proc.auxv: %d: %d", kipp->ki_pid, errno);
-		return;
+		warn("sysctl: kern.proc.auxv: %d: %d", pid, errno);
+		return (0);
 	}
-	if (error < 0 || len == 0)
-		return;
-	if (len == 0) {
-		printf(" -\n");
+	return (len);
+}
+
+void
+procstat_auxv(struct kinfo_proc *kipp)
+{
+	size_t len, i;
+
+	if (!hflag)
+		printf("%5s %-16s %-16s %-16s\n", "PID", "COMM", "AUXV", "VALUE");
+	len = retrieve_auxv(kipp->ki_pid);
+	if (len == 0)
 		return;
-	}
 	snprintf(prefix, sizeof(prefix), "%5d %-16s", kipp->ki_pid,
 	    kipp->ki_comm);
 	for (i = 0; i < len; i++) {