diff options
| -rw-r--r-- | lib/Kconfig | 14 | ||||
| -rw-r--r-- | lib/glob.c | 164 |
2 files changed, 178 insertions, 0 deletions
diff --git a/lib/Kconfig b/lib/Kconfig index 41bfeec72e40..df872659ddd3 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -415,6 +415,20 @@ config GLOB are compiling an out-of tree driver which tells you that it depends on this. +config GLOB_SELFTEST + bool "glob self-test on init" + default n + depends on GLOB + help + This option enables a simple self-test of the glob_match + function on startup. It is primarily useful for people + working on the code to ensure they haven't introduced any + regressions. + + It only adds a little bit of code and slows kernel boot (or + module load) by a small amount, so you're welcome to play with + it, but you probably don't need it. + # # Netlink attribute parsing support is select'ed if needed # diff --git a/lib/glob.c b/lib/glob.c index 0ba3ea86b546..500fc80d23e1 100644 --- a/lib/glob.c +++ b/lib/glob.c @@ -121,3 +121,167 @@ backtrack: } } EXPORT_SYMBOL(glob_match); + + +#ifdef CONFIG_GLOB_SELFTEST + +#include <linux/printk.h> +#include <linux/moduleparam.h> + +/* Boot with "glob.verbose=1" to show successful tests, too */ +static bool verbose = false; +module_param(verbose, bool, 0); + +struct glob_test { + char const *pat, *str; + bool expected; +}; + +static bool __pure __init test(char const *pat, char const *str, bool expected) +{ + bool match = glob_match(pat, str); + bool success = match == expected; + + /* Can't get string literals into a particular section, so... */ + static char const msg_error[] __initconst = + KERN_ERR "glob: \"%s\" vs. \"%s\": %s *** ERROR ***\n"; + static char const msg_ok[] __initconst = + KERN_DEBUG "glob: \"%s\" vs. \"%s\": %s OK\n"; + static char const mismatch[] __initconst = "mismatch"; + char const *message; + + if (!success) + message = msg_error; + else if (verbose) + message = msg_ok; + else + return success; + + printk(message, pat, str, mismatch + 3*match); + return success; +} + +/* + * The tests are all jammed together in one array to make it simpler + * to place that array in the .init.rodata section. The obvious + * "array of structures containing char *" has no way to force the + * pointed-to strings to be in a particular section. + * + * Anyway, a test consists of: + * 1. Expected glob_match result: '1' or '0'. + * 2. Pattern to match: null-terminated string + * 3. String to match against: null-terminated string + * + * The list of tests is terminated with a final '\0' instead of + * a glob_match result character. + */ +static char const glob_tests[] __initconst = + /* Some basic tests */ + "1" "a\0" "a\0" + "0" "a\0" "b\0" + "0" "a\0" "aa\0" + "0" "a\0" "\0" + "1" "\0" "\0" + "0" "\0" "a\0" + /* Simple character class tests */ + "1" "[a]\0" "a\0" + "0" "[a]\0" "b\0" + "0" "[!a]\0" "a\0" + "1" "[!a]\0" "b\0" + "1" "[ab]\0" "a\0" + "1" "[ab]\0" "b\0" + "0" "[ab]\0" "c\0" + "1" "[!ab]\0" "c\0" + "1" "[a-c]\0" "b\0" + "0" "[a-c]\0" "d\0" + /* Corner cases in character class parsing */ + "1" "[a-c-e-g]\0" "-\0" + "0" "[a-c-e-g]\0" "d\0" + "1" "[a-c-e-g]\0" "f\0" + "1" "[]a-ceg-ik[]\0" "a\0" + "1" "[]a-ceg-ik[]\0" "]\0" + "1" "[]a-ceg-ik[]\0" "[\0" + "1" "[]a-ceg-ik[]\0" "h\0" + "0" "[]a-ceg-ik[]\0" "f\0" + "0" "[!]a-ceg-ik[]\0" "h\0" + "0" "[!]a-ceg-ik[]\0" "]\0" + "1" "[!]a-ceg-ik[]\0" "f\0" + /* Simple wild cards */ + "1" "?\0" "a\0" + "0" "?\0" "aa\0" + "0" "??\0" "a\0" + "1" "?x?\0" "axb\0" + "0" "?x?\0" "abx\0" + "0" "?x?\0" "xab\0" + /* Asterisk wild cards (backtracking) */ + "0" "*??\0" "a\0" + "1" "*??\0" "ab\0" + "1" "*??\0" "abc\0" + "1" "*??\0" "abcd\0" + "0" "??*\0" "a\0" + "1" "??*\0" "ab\0" + "1" "??*\0" "abc\0" + "1" "??*\0" "abcd\0" + "0" "?*?\0" "a\0" + "1" "?*?\0" "ab\0" + "1" "?*?\0" "abc\0" + "1" "?*?\0" "abcd\0" + "1" "*b\0" "b\0" + "1" "*b\0" "ab\0" + "0" "*b\0" "ba\0" + "1" "*b\0" "bb\0" + "1" "*b\0" "abb\0" + "1" "*b\0" "bab\0" + "1" "*bc\0" "abbc\0" + "1" "*bc\0" "bc\0" + "1" "*bc\0" "bbc\0" + "1" "*bc\0" "bcbc\0" + /* Multiple asterisks (complex backtracking) */ + "1" "*ac*\0" "abacadaeafag\0" + "1" "*ac*ae*ag*\0" "abacadaeafag\0" + "1" "*a*b*[bc]*[ef]*g*\0" "abacadaeafag\0" + "0" "*a*b*[ef]*[cd]*g*\0" "abacadaeafag\0" + "1" "*abcd*\0" "abcabcabcabcdefg\0" + "1" "*ab*cd*\0" "abcabcabcabcdefg\0" + "1" "*abcd*abcdef*\0" "abcabcdabcdeabcdefg\0" + "0" "*abcd*\0" "abcabcabcabcefg\0" + "0" "*ab*cd*\0" "abcabcabcabcefg\0"; + +static int __init glob_init(void) +{ + unsigned successes = 0; + unsigned n = 0; + char const *p = glob_tests; + static char const message[] __initconst = + KERN_INFO "glob: %u self-tests passed, %u failed\n"; + + /* + * Tests are jammed together in a string. The first byte is '1' + * or '0' to indicate the expected outcome, or '\0' to indicate the + * end of the tests. Then come two null-terminated strings: the + * pattern and the string to match it against. + */ + while (*p) { + bool expected = *p++ & 1; + char const *pat = p; + + p += strlen(p) + 1; + successes += test(pat, p, expected); + p += strlen(p) + 1; + n++; + } + + n -= successes; + printk(message, successes, n); + + /* What's the errno for "kernel bug detected"? Guess... */ + return n ? -ECANCELED : 0; +} + +/* We need a dummy exit function to allow unload */ +static void __exit glob_fini(void) { } + +module_init(glob_init); +module_exit(glob_fini); + +#endif /* CONFIG_GLOB_SELFTEST */ |