Create detect_container() and detect_vm() functions

These functions replace rc_sys so that we can detect containers and vms
separately.

Also, we copy file_regex() to rc-misc.c and open it to all operating
systems.

src/includes/rc-misc.h

@@ -87,4 +87,8 @@ int is_writable(const char *);
 #define service_stop(service)  exec_service(service, "stop");
 
 int parse_mode(mode_t *, char *);
+const char *detect_prefix(void);
+const char *get_systype(void);
+const char *detect_container(void);
+const char *detect_vm(void);
 #endif

src/rc/rc-misc.c

@@ -34,12 +34,12 @@
 
 #ifdef __linux__
 #  include <sys/sysinfo.h>
-#  include <regex.h>
 #endif
 
 #include <ctype.h>
 #include <fcntl.h>
 #include <limits.h>
+#  include <regex.h>
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -346,3 +346,160 @@ is_writable(const char *path)
 
 	return 0;
 }
+
+static bool file_regex(const char *file, const char *regex)
+{
+	FILE *fp;
+	char *line = NULL;
+	size_t len = 0;
+	regex_t re;
+	bool retval = true;
+	int result;
+
+	if (!(fp = fopen(file, "r")))
+		return false;
+
+	if ((result = regcomp(&re, regex, REG_EXTENDED | REG_NOSUB)) != 0) {
+		fclose(fp);
+		line = xmalloc(sizeof(char) * BUFSIZ);
+		regerror(result, &re, line, BUFSIZ);
+		fprintf(stderr, "file_regex: %s", line);
+		free(line);
+		return false;
+	}
+
+	while ((rc_getline(&line, &len, fp))) {
+		char *str = line;
+		/* some /proc files have \0 separated content so we have to
+		   loop through the 'line' */
+		do {
+			if (regexec(&re, str, 0, NULL, 0) == 0)
+				goto found;
+			str += strlen(str) + 1;
+			/* len is the size of allocated buffer and we don't
+			   want call regexec BUFSIZE times. find next str */
+			while (str < line + len && *str == '\0')
+				str++;
+		} while (str < line + len);
+	}
+	retval = false;
+found:
+	fclose(fp);
+	free(line);
+	regfree(&re);
+
+	return retval;
+}
+
+const char *detect_prefix(void)
+{
+#ifdef PREFIX
+	return RC_SYS_PREFIX;
+#else
+	return NULL;
+#endif
+}
+
+const char *get_systype(void)
+{
+	char *systype = rc_conf_value("rc_sys");
+	if (systype) {
+		char *s = systype;
+		/* Convert to uppercase */
+		while (s && *s) {
+			if (islower((unsigned char) *s))
+				*s = toupper((unsigned char) *s);
+			s++;
+		}
+	}
+	return systype;
+}
+
+const char *detect_container(void)
+{
+	char *systype = get_systype();
+
+#ifdef __FreeBSD__
+	if (systype && strcmp(systype, RC_SYS_JAIL) == 0)
+		return RC_SYS_JAIL;
+	int jailed = 0;
+	size_t len = sizeof(jailed);
+
+	if (sysctlbyname("security.jail.jailed", &jailed, &len, NULL, 0) == 0)
+		if (jailed == 1)
+			return RC_SYS_JAIL;
+#endif
+
+#ifdef __linux__
+	if (systype) {
+		if (strcmp(systype, RC_SYS_UML) == 0)
+			return RC_SYS_UML;
+		if (strcmp(systype, RC_SYS_VSERVER) == 0)
+			return RC_SYS_VSERVER;
+		if (strcmp(systype, RC_SYS_OPENVZ) == 0)
+			return RC_SYS_OPENVZ;
+		if (strcmp(systype, RC_SYS_LXC) == 0)
+			return RC_SYS_LXC;
+		if (strcmp(systype, RC_SYS_RKT) == 0)
+				return RC_SYS_RKT;
+		if (strcmp(systype, RC_SYS_SYSTEMD_NSPAWN) == 0)
+				return RC_SYS_SYSTEMD_NSPAWN;
+		if (strcmp(systype, RC_SYS_DOCKER) == 0)
+				return RC_SYS_DOCKER;
+	}
+	if (file_regex("/proc/cpuinfo", "UML"))
+		return RC_SYS_UML;
+	else if (file_regex("/proc/self/status",
+		"(s_context|VxID):[[:space:]]*[1-9]"))
+		return RC_SYS_VSERVER;
+	else if (exists("/proc/vz/veinfo") && !exists("/proc/vz/version"))
+		return RC_SYS_OPENVZ;
+	else if (file_regex("/proc/self/status",
+		"envID:[[:space:]]*[1-9]"))
+		return RC_SYS_OPENVZ; /* old test */
+	else if (file_regex("/proc/1/environ", "container=lxc"))
+		return RC_SYS_LXC;
+	else if (file_regex("/proc/1/environ", "container=rkt"))
+		return RC_SYS_RKT;
+	else if (file_regex("/proc/1/environ", "container=systemd-nspawn"))
+		return RC_SYS_SYSTEMD_NSPAWN;
+	else if (file_regex("/proc/1/environ", "container=docker"))
+		return RC_SYS_DOCKER;
+#endif
+
+	return NULL;
+}
+
+const char *detect_vm(void)
+{
+	char *systype = get_systype();
+
+#ifdef __NetBSD__
+	if (systype) {
+		if(strcmp(systype, RC_SYS_XEN0) == 0)
+				return RC_SYS_XEN0;
+		if (strcmp(systype, RC_SYS_XENU) == 0)
+			return RC_SYS_XENU;
+	}
+	if (exists("/kern/xen/privcmd"))
+		return RC_SYS_XEN0;
+	if (exists("/kern/xen"))
+		return RC_SYS_XENU;
+#endif
+
+#ifdef __linux__
+	if (systype) {
+		if (strcmp(systype, RC_SYS_XEN0) == 0)
+			return RC_SYS_XEN0;
+		if (strcmp(systype, RC_SYS_XENU) == 0)
+			return RC_SYS_XENU;
+	}
+	if (exists("/proc/xen")) {
+		if (file_regex("/proc/xen/capabilities", "control_d"))
+			return RC_SYS_XEN0;
+		return RC_SYS_XENU;
+	}
+#endif
+
+	return NULL;
+}