libmount: add private mnt_get_kernel_cmdline_option()

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/include/pathnames.h b/include/pathnames.h
index 58bba519a37fecc28954285b9f7206926ee08833..a7f33fed592cc008ab17f187495c085f7be4a014 100644 (file)
--- a/include/pathnames.h
+++ b/include/pathnames.h
@@ -152,5 +152,8 @@
 /* wdctl path */
 #define _PATH_WATCHDOG_DEV     "/dev/watchdog"
 
+/* kernel command line */
+#define _PATH_PROC_CMDLINE     "/proc/cmdline"
+
 #endif /* PATHNAMES_H */
 

diff --git a/libmount/src/mountP.h b/libmount/src/mountP.h
index bbaa2c6c4d484adc072c31bcbbd90db3f8dd61fc..f28935d0d06065b4b72ee380e8c070bff42a3d44 100644 (file)
--- a/libmount/src/mountP.h
+++ b/libmount/src/mountP.h
@@ -147,6 +147,8 @@ extern const char *mnt_get_utab_path(void);
 extern int mnt_get_filesystems(char ***filesystems, const char *pattern);
 extern void mnt_free_filesystems(char **filesystems);
 
+extern char *mnt_get_kernel_cmdline_option(const char *name);
+
 /* tab.c */
 extern int mnt_table_set_parser_fltrcb(        struct libmnt_table *tb,
                                        int (*cb)(struct libmnt_fs *, void *),

diff --git a/libmount/src/utils.c b/libmount/src/utils.c
index 0cfefb3474f9cdd24a6cbc88784bda0cb48e2ea2..624633dd85cbfb46410ea7faeaaa8ce805497dbf 100644 (file)
--- a/libmount/src/utils.c
+++ b/libmount/src/utils.c
@@ -881,6 +881,78 @@ char *mnt_get_fs_root(const char *path, const char *mnt)
        return res;
 }
 
+/*
+ * Search for @name kernel command parametr.
+ *
+ * Returns newly allocated string with parameter argument if the @name is
+ * specified as "name=" or returns pointer to @name or returns NULL if not
+ * found.
+ *
+ * For example cmdline: "aaa bbb=BBB ccc"
+ *
+ *     @name is "aaa"  --returns--> "aaa" (pointer to @name)
+ *     @name is "bbb=" --returns--> "BBB" (allocated)
+ *     @name is "foo"  --returns--> NULL
+ */
+char *mnt_get_kernel_cmdline_option(const char *name)
+{
+       FILE *f;
+       size_t len;
+       int val = 0;
+       char *p, *res = NULL;
+       char buf[BUFSIZ];       /* see kernel include/asm-generic/setup.h: COMMAND_LINE_SIZE */
+       const char *path = _PATH_PROC_CMDLINE;
+
+       assert(name);
+       assert(*name);
+
+#ifdef TEST_PROGRAM
+       path = safe_getenv("LIBMOUNT_KERNEL_CMDLINE");
+       if (!path)
+               path = _PATH_PROC_CMDLINE;
+#endif
+       f = fopen(path, "r");
+       if (!f)
+               return NULL;
+
+       p = fgets(buf, sizeof(buf), f);
+       fclose(f);
+
+       if (!p || !*p || *p == '\n')
+               return NULL;
+
+       len = strlen(buf);
+       *(buf + len - 1) = '\0';        /* remove last '\n' */
+
+       len = strlen(name);
+       if (len && *(name + len - 1) == '=')
+               val = 1;
+
+       while (p && *p) {
+               if (p != buf)
+                       p++;
+               if (!(p = strstr(p, name)))
+                       break;                  /* not found the option */
+               if (p != buf && !isblank(*(p - 1)))
+                       continue;               /* no space before the option */
+               if (!val && *(p + len) != '\0' && !isblank(*(p + len)))
+                       continue;               /* no space behind the option */
+               if (val) {
+                       char *v = p + len;
+
+                       while (*p && !isblank(*p))      /* jump to the end of the argument */
+                               p++;
+                       *p = '\0';
+                       res = strdup(v);
+                       break;
+               } else
+                       res = (char *) name;    /* option without '=' */
+               break;
+       }
+
+       return res;
+}
+
 #ifdef TEST_PROGRAM
 int test_match_fstype(struct libmnt_test *ts, int argc, char *argv[])
 {
@@ -974,6 +1046,24 @@ int test_chdir(struct libmnt_test *ts, int argc, char *argv[])
        return rc;
 }
 
+int test_kernel_cmdline(struct libmnt_test *ts, int argc, char *argv[])
+{
+       char *name = argv[1];
+       char *res;
+
+       res = mnt_get_kernel_cmdline_option(name);
+       if (!res)
+               printf("'%s' not found\n", name);
+       else if (res == name)
+               printf("'%s' found\n", name);
+       else {
+               printf("'%s' found, argument: '%s'\n", name, res);
+               free(res);
+       }
+
+       return 0;
+}
+
 
 int main(int argc, char *argv[])
 {
@@ -986,6 +1076,7 @@ int main(int argc, char *argv[])
        { "--mountpoint",    test_mountpoint,      "<path>" },
        { "--fs-root",       test_fsroot,          "<path>" },
        { "--cd-parent",     test_chdir,           "<path>" },
+       { "--kernel-cmdline",test_kernel_cmdline,  "<option> | <option>=" },
        { NULL }
        };
 

diff --git a/tests/expected/libmount/utils-kernel-cmdline b/tests/expected/libmount/utils-kernel-cmdline
new file mode 100644 (file)
index 0000000..2a63165
--- /dev/null
+++ b/tests/expected/libmount/utils-kernel-cmdline
@@ -0,0 +1,5 @@
+'selinux=' found, argument: '0'
+'selinux' not found
+'ro' found
+'ro=' not found
+'root=' found, argument: 'UUID=33230ae2-1093-4353-824c-f7ca09a2a882'

diff --git a/tests/ts/libmount/files/kernel_cmdline b/tests/ts/libmount/files/kernel_cmdline
new file mode 100644 (file)
index 0000000..37a0c89
--- /dev/null
+++ b/tests/ts/libmount/files/kernel_cmdline
@@ -0,0 +1 @@
+rd.md=0 rd.lvm=0 rd.dm=0  KEYTABLE=us root=UUID=33230ae2-1093-4353-824c-f7ca09a2a882 rd.luks=0 SYSFONT=latarcyrheb-sun16 ro LANG=en_US.UTF-8 selinux=0

diff --git a/tests/ts/libmount/utils b/tests/ts/libmount/utils
index d425400adfe85d707877db6e5ffcf4ca670c1324..6facaad103ff39b2b00f1bc0911e94ece3fcf304 100755 (executable)
--- a/tests/ts/libmount/utils
+++ b/tests/ts/libmount/utils
@@ -76,4 +76,13 @@ ts_init_subtest "fs-root-subdir2"
 ts_valgrind $TESTPROG --fs-root /etc &> $TS_OUTPUT
 ts_finalize_subtest
 
+ts_init_subtest "kernel-cmdline"
+export LIBMOUNT_KERNEL_CMDLINE="$TS_SELF/files/kernel_cmdline"
+ts_valgrind $TESTPROG --kernel-cmdline selinux= &>> $TS_OUTPUT
+ts_valgrind $TESTPROG --kernel-cmdline selinux &>> $TS_OUTPUT
+ts_valgrind $TESTPROG --kernel-cmdline ro &>> $TS_OUTPUT
+ts_valgrind $TESTPROG --kernel-cmdline ro= &>> $TS_OUTPUT
+ts_valgrind $TESTPROG --kernel-cmdline root= &>> $TS_OUTPUT
+ts_finalize_subtest
+
 ts_finalize