diff options
Diffstat (limited to 'tools/testing/selftests/proc')
-rw-r--r-- | tools/testing/selftests/proc/.gitignore | 8 | ||||
-rw-r--r-- | tools/testing/selftests/proc/Makefile | 13 | ||||
-rw-r--r-- | tools/testing/selftests/proc/config | 1 | ||||
-rw-r--r-- | tools/testing/selftests/proc/proc-loadavg-001.c | 83 | ||||
-rw-r--r-- | tools/testing/selftests/proc/proc-self-map-files-001.c | 82 | ||||
-rw-r--r-- | tools/testing/selftests/proc/proc-self-map-files-002.c | 85 | ||||
-rw-r--r-- | tools/testing/selftests/proc/proc-self-syscall.c | 45 | ||||
-rw-r--r-- | tools/testing/selftests/proc/proc-self-wchan.c | 25 | ||||
-rw-r--r-- | tools/testing/selftests/proc/proc-uptime-001.c | 45 | ||||
-rw-r--r-- | tools/testing/selftests/proc/proc-uptime-002.c | 79 | ||||
-rw-r--r-- | tools/testing/selftests/proc/proc-uptime.h | 74 | ||||
-rw-r--r-- | tools/testing/selftests/proc/read.c | 147 |
12 files changed, 687 insertions, 0 deletions
diff --git a/tools/testing/selftests/proc/.gitignore b/tools/testing/selftests/proc/.gitignore new file mode 100644 index 000000000000..6c16f77c722c --- /dev/null +++ b/tools/testing/selftests/proc/.gitignore @@ -0,0 +1,8 @@ +/proc-loadavg-001 +/proc-self-map-files-001 +/proc-self-map-files-002 +/proc-self-syscall +/proc-self-wchan +/proc-uptime-001 +/proc-uptime-002 +/read diff --git a/tools/testing/selftests/proc/Makefile b/tools/testing/selftests/proc/Makefile new file mode 100644 index 000000000000..dbb87e56264c --- /dev/null +++ b/tools/testing/selftests/proc/Makefile @@ -0,0 +1,13 @@ +CFLAGS += -Wall -O2 + +TEST_GEN_PROGS := +TEST_GEN_PROGS += proc-loadavg-001 +TEST_GEN_PROGS += proc-self-map-files-001 +TEST_GEN_PROGS += proc-self-map-files-002 +TEST_GEN_PROGS += proc-self-syscall +TEST_GEN_PROGS += proc-self-wchan +TEST_GEN_PROGS += proc-uptime-001 +TEST_GEN_PROGS += proc-uptime-002 +TEST_GEN_PROGS += read + +include ../lib.mk diff --git a/tools/testing/selftests/proc/config b/tools/testing/selftests/proc/config new file mode 100644 index 000000000000..68fbd2b35884 --- /dev/null +++ b/tools/testing/selftests/proc/config @@ -0,0 +1 @@ +CONFIG_PROC_FS=y diff --git a/tools/testing/selftests/proc/proc-loadavg-001.c b/tools/testing/selftests/proc/proc-loadavg-001.c new file mode 100644 index 000000000000..e38ad6d94d4b --- /dev/null +++ b/tools/testing/selftests/proc/proc-loadavg-001.c @@ -0,0 +1,83 @@ +/* + * Copyright _ 2018 Alexey Dobriyan <adobriyan@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +/* Test that /proc/loadavg correctly reports last pid in pid namespace. */ +#define _GNU_SOURCE +#include <errno.h> +#include <sched.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> +#include <sys/wait.h> + +int main(void) +{ + pid_t pid; + int wstatus; + + if (unshare(CLONE_NEWPID) == -1) { + if (errno == ENOSYS || errno == EPERM) + return 2; + return 1; + } + + pid = fork(); + if (pid == -1) + return 1; + if (pid == 0) { + char buf[128], *p; + int fd; + ssize_t rv; + + fd = open("/proc/loadavg" , O_RDONLY); + if (fd == -1) + return 1; + rv = read(fd, buf, sizeof(buf)); + if (rv < 3) + return 1; + p = buf + rv; + + /* pid 1 */ + if (!(p[-3] == ' ' && p[-2] == '1' && p[-1] == '\n')) + return 1; + + pid = fork(); + if (pid == -1) + return 1; + if (pid == 0) + return 0; + if (waitpid(pid, NULL, 0) == -1) + return 1; + + lseek(fd, 0, SEEK_SET); + rv = read(fd, buf, sizeof(buf)); + if (rv < 3) + return 1; + p = buf + rv; + + /* pid 2 */ + if (!(p[-3] == ' ' && p[-2] == '2' && p[-1] == '\n')) + return 1; + + return 0; + } + + if (waitpid(pid, &wstatus, 0) == -1) + return 1; + if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) == 0) + return 0; + return 1; +} diff --git a/tools/testing/selftests/proc/proc-self-map-files-001.c b/tools/testing/selftests/proc/proc-self-map-files-001.c new file mode 100644 index 000000000000..af1d0a6af810 --- /dev/null +++ b/tools/testing/selftests/proc/proc-self-map-files-001.c @@ -0,0 +1,82 @@ +/* + * Copyright _ 2018 Alexey Dobriyan <adobriyan@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +/* Test readlink /proc/self/map_files/... */ +#include <errno.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <stdio.h> +#include <unistd.h> +#include <sys/mman.h> +#include <stdlib.h> + +static void pass(const char *fmt, unsigned long a, unsigned long b) +{ + char name[64]; + char buf[64]; + + snprintf(name, sizeof(name), fmt, a, b); + if (readlink(name, buf, sizeof(buf)) == -1) + exit(1); +} + +static void fail(const char *fmt, unsigned long a, unsigned long b) +{ + char name[64]; + char buf[64]; + + snprintf(name, sizeof(name), fmt, a, b); + if (readlink(name, buf, sizeof(buf)) == -1 && errno == ENOENT) + return; + exit(1); +} + +int main(void) +{ + const unsigned int PAGE_SIZE = sysconf(_SC_PAGESIZE); + void *p; + int fd; + unsigned long a, b; + + fd = open("/dev/zero", O_RDONLY); + if (fd == -1) + return 1; + + p = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE, fd, 0); + if (p == MAP_FAILED) + return 1; + + a = (unsigned long)p; + b = (unsigned long)p + PAGE_SIZE; + + pass("/proc/self/map_files/%lx-%lx", a, b); + fail("/proc/self/map_files/ %lx-%lx", a, b); + fail("/proc/self/map_files/%lx -%lx", a, b); + fail("/proc/self/map_files/%lx- %lx", a, b); + fail("/proc/self/map_files/%lx-%lx ", a, b); + fail("/proc/self/map_files/0%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-0%lx", a, b); + if (sizeof(long) == 4) { + fail("/proc/self/map_files/100000000%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-100000000%lx", a, b); + } else if (sizeof(long) == 8) { + fail("/proc/self/map_files/10000000000000000%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-10000000000000000%lx", a, b); + } else + return 1; + + return 0; +} diff --git a/tools/testing/selftests/proc/proc-self-map-files-002.c b/tools/testing/selftests/proc/proc-self-map-files-002.c new file mode 100644 index 000000000000..aebf4be56111 --- /dev/null +++ b/tools/testing/selftests/proc/proc-self-map-files-002.c @@ -0,0 +1,85 @@ +/* + * Copyright _ 2018 Alexey Dobriyan <adobriyan@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +/* Test readlink /proc/self/map_files/... with address 0. */ +#include <errno.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <stdio.h> +#include <unistd.h> +#include <sys/mman.h> +#include <stdlib.h> + +static void pass(const char *fmt, unsigned long a, unsigned long b) +{ + char name[64]; + char buf[64]; + + snprintf(name, sizeof(name), fmt, a, b); + if (readlink(name, buf, sizeof(buf)) == -1) + exit(1); +} + +static void fail(const char *fmt, unsigned long a, unsigned long b) +{ + char name[64]; + char buf[64]; + + snprintf(name, sizeof(name), fmt, a, b); + if (readlink(name, buf, sizeof(buf)) == -1 && errno == ENOENT) + return; + exit(1); +} + +int main(void) +{ + const unsigned int PAGE_SIZE = sysconf(_SC_PAGESIZE); + void *p; + int fd; + unsigned long a, b; + + fd = open("/dev/zero", O_RDONLY); + if (fd == -1) + return 1; + + p = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE|MAP_FIXED, fd, 0); + if (p == MAP_FAILED) { + if (errno == EPERM) + return 2; + return 1; + } + + a = (unsigned long)p; + b = (unsigned long)p + PAGE_SIZE; + + pass("/proc/self/map_files/%lx-%lx", a, b); + fail("/proc/self/map_files/ %lx-%lx", a, b); + fail("/proc/self/map_files/%lx -%lx", a, b); + fail("/proc/self/map_files/%lx- %lx", a, b); + fail("/proc/self/map_files/%lx-%lx ", a, b); + fail("/proc/self/map_files/0%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-0%lx", a, b); + if (sizeof(long) == 4) { + fail("/proc/self/map_files/100000000%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-100000000%lx", a, b); + } else if (sizeof(long) == 8) { + fail("/proc/self/map_files/10000000000000000%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-10000000000000000%lx", a, b); + } else + return 1; + + return 0; +} diff --git a/tools/testing/selftests/proc/proc-self-syscall.c b/tools/testing/selftests/proc/proc-self-syscall.c new file mode 100644 index 000000000000..05eb6f91f1e9 --- /dev/null +++ b/tools/testing/selftests/proc/proc-self-syscall.c @@ -0,0 +1,45 @@ +#define _GNU_SOURCE +#include <unistd.h> +#include <sys/syscall.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <errno.h> +#include <unistd.h> +#include <string.h> +#include <stdio.h> + +static inline ssize_t sys_read(int fd, void *buf, size_t len) +{ + return syscall(SYS_read, fd, buf, len); +} + +int main(void) +{ + char buf1[64]; + char buf2[64]; + int fd; + ssize_t rv; + + fd = open("/proc/self/syscall", O_RDONLY); + if (fd == -1) { + if (errno == ENOENT) + return 2; + return 1; + } + + /* Do direct system call as libc can wrap anything. */ + snprintf(buf1, sizeof(buf1), "%ld 0x%lx 0x%lx 0x%lx", + (long)SYS_read, (long)fd, (long)buf2, (long)sizeof(buf2)); + + memset(buf2, 0, sizeof(buf2)); + rv = sys_read(fd, buf2, sizeof(buf2)); + if (rv < 0) + return 1; + if (rv < strlen(buf1)) + return 1; + if (strncmp(buf1, buf2, strlen(buf1)) != 0) + return 1; + + return 0; +} diff --git a/tools/testing/selftests/proc/proc-self-wchan.c b/tools/testing/selftests/proc/proc-self-wchan.c new file mode 100644 index 000000000000..b8d8728a6869 --- /dev/null +++ b/tools/testing/selftests/proc/proc-self-wchan.c @@ -0,0 +1,25 @@ +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <errno.h> +#include <unistd.h> + +int main(void) +{ + char buf[64]; + int fd; + + fd = open("/proc/self/wchan", O_RDONLY); + if (fd == -1) { + if (errno == ENOENT) + return 2; + return 1; + } + + buf[0] = '\0'; + if (read(fd, buf, sizeof(buf)) != 1) + return 1; + if (buf[0] != '0') + return 1; + return 0; +} diff --git a/tools/testing/selftests/proc/proc-uptime-001.c b/tools/testing/selftests/proc/proc-uptime-001.c new file mode 100644 index 000000000000..303f26092306 --- /dev/null +++ b/tools/testing/selftests/proc/proc-uptime-001.c @@ -0,0 +1,45 @@ +/* + * Copyright _ 2018 Alexey Dobriyan <adobriyan@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +// Test that values in /proc/uptime increment monotonically. +#undef NDEBUG +#include <assert.h> +#include <stdint.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> + +#include "proc-uptime.h" + +int main(void) +{ + uint64_t start, u0, u1, i0, i1; + int fd; + + fd = open("/proc/uptime", O_RDONLY); + assert(fd >= 0); + + proc_uptime(fd, &u0, &i0); + start = u0; + do { + proc_uptime(fd, &u1, &i1); + assert(u1 >= u0); + assert(i1 >= i0); + u0 = u1; + i0 = i1; + } while (u1 - start < 100); + + return 0; +} diff --git a/tools/testing/selftests/proc/proc-uptime-002.c b/tools/testing/selftests/proc/proc-uptime-002.c new file mode 100644 index 000000000000..0cb79e1f1674 --- /dev/null +++ b/tools/testing/selftests/proc/proc-uptime-002.c @@ -0,0 +1,79 @@ +/* + * Copyright _ 2018 Alexey Dobriyan <adobriyan@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +// Test that values in /proc/uptime increment monotonically +// while shifting across CPUs. +#define _GNU_SOURCE +#undef NDEBUG +#include <assert.h> +#include <unistd.h> +#include <sys/syscall.h> +#include <stdlib.h> +#include <string.h> + +#include <stdint.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> + +#include "proc-uptime.h" + +static inline int sys_sched_getaffinity(pid_t pid, unsigned int len, unsigned long *m) +{ + return syscall(SYS_sched_getaffinity, pid, len, m); +} + +static inline int sys_sched_setaffinity(pid_t pid, unsigned int len, unsigned long *m) +{ + return syscall(SYS_sched_setaffinity, pid, len, m); +} + +int main(void) +{ + unsigned int len; + unsigned long *m; + unsigned int cpu; + uint64_t u0, u1, i0, i1; + int fd; + + /* find out "nr_cpu_ids" */ + m = NULL; + len = 0; + do { + len += sizeof(unsigned long); + free(m); + m = malloc(len); + } while (sys_sched_getaffinity(0, len, m) == -EINVAL); + + fd = open("/proc/uptime", O_RDONLY); + assert(fd >= 0); + + proc_uptime(fd, &u0, &i0); + for (cpu = 0; cpu < len * 8; cpu++) { + memset(m, 0, len); + m[cpu / (8 * sizeof(unsigned long))] |= 1UL << (cpu % (8 * sizeof(unsigned long))); + + /* CPU might not exist, ignore error */ + sys_sched_setaffinity(0, len, m); + + proc_uptime(fd, &u1, &i1); + assert(u1 >= u0); + assert(i1 >= i0); + u0 = u1; + i0 = i1; + } + + return 0; +} diff --git a/tools/testing/selftests/proc/proc-uptime.h b/tools/testing/selftests/proc/proc-uptime.h new file mode 100644 index 000000000000..d584419f50a7 --- /dev/null +++ b/tools/testing/selftests/proc/proc-uptime.h @@ -0,0 +1,74 @@ +/* + * Copyright _ 2018 Alexey Dobriyan <adobriyan@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +#undef NDEBUG +#include <assert.h> +#include <errno.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> + +static unsigned long long xstrtoull(const char *p, char **end) +{ + if (*p == '0') { + *end = (char *)p + 1; + return 0; + } else if ('1' <= *p && *p <= '9') { + unsigned long long val; + + errno = 0; + val = strtoull(p, end, 10); + assert(errno == 0); + return val; + } else + assert(0); +} + +static void proc_uptime(int fd, uint64_t *uptime, uint64_t *idle) +{ + uint64_t val1, val2; + char buf[64], *p; + ssize_t rv; + + /* save "p < end" checks */ + memset(buf, 0, sizeof(buf)); + rv = pread(fd, buf, sizeof(buf), 0); + assert(0 <= rv && rv <= sizeof(buf)); + buf[sizeof(buf) - 1] = '\0'; + + p = buf; + + val1 = xstrtoull(p, &p); + assert(p[0] == '.'); + assert('0' <= p[1] && p[1] <= '9'); + assert('0' <= p[2] && p[2] <= '9'); + assert(p[3] == ' '); + + val2 = (p[1] - '0') * 10 + p[2] - '0'; + *uptime = val1 * 100 + val2; + + p += 4; + + val1 = xstrtoull(p, &p); + assert(p[0] == '.'); + assert('0' <= p[1] && p[1] <= '9'); + assert('0' <= p[2] && p[2] <= '9'); + assert(p[3] == '\n'); + + val2 = (p[1] - '0') * 10 + p[2] - '0'; + *idle = val1 * 100 + val2; + + assert(p + 4 == buf + rv); +} diff --git a/tools/testing/selftests/proc/read.c b/tools/testing/selftests/proc/read.c new file mode 100644 index 000000000000..12e397f78592 --- /dev/null +++ b/tools/testing/selftests/proc/read.c @@ -0,0 +1,147 @@ +/* + * Copyright _ 2018 Alexey Dobriyan <adobriyan@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +// Test +// 1) read of every file in /proc +// 2) readlink of every symlink in /proc +// 3) recursively (1) + (2) for every directory in /proc +// 4) write to /proc/*/clear_refs and /proc/*/task/*/clear_refs +// 5) write to /proc/sysrq-trigger +#undef NDEBUG +#include <assert.h> +#include <errno.h> +#include <sys/types.h> +#include <dirent.h> +#include <stdbool.h> +#include <stdlib.h> +#include <string.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> + +static inline bool streq(const char *s1, const char *s2) +{ + return strcmp(s1, s2) == 0; +} + +static struct dirent *xreaddir(DIR *d) +{ + struct dirent *de; + + errno = 0; + de = readdir(d); + if (!de && errno != 0) { + exit(1); + } + return de; +} + +static void f_reg(DIR *d, const char *filename) +{ + char buf[4096]; + int fd; + ssize_t rv; + + /* read from /proc/kmsg can block */ + fd = openat(dirfd(d), filename, O_RDONLY|O_NONBLOCK); + if (fd == -1) + return; + rv = read(fd, buf, sizeof(buf)); + assert((0 <= rv && rv <= sizeof(buf)) || rv == -1); + close(fd); +} + +static void f_reg_write(DIR *d, const char *filename, const char *buf, size_t len) +{ + int fd; + ssize_t rv; + + fd = openat(dirfd(d), filename, O_WRONLY); + if (fd == -1) + return; + rv = write(fd, buf, len); + assert((0 <= rv && rv <= len) || rv == -1); + close(fd); +} + +static void f_lnk(DIR *d, const char *filename) +{ + char buf[4096]; + ssize_t rv; + + rv = readlinkat(dirfd(d), filename, buf, sizeof(buf)); + assert((0 <= rv && rv <= sizeof(buf)) || rv == -1); +} + +static void f(DIR *d, unsigned int level) +{ + struct dirent *de; + + de = xreaddir(d); + assert(de->d_type == DT_DIR); + assert(streq(de->d_name, ".")); + + de = xreaddir(d); + assert(de->d_type == DT_DIR); + assert(streq(de->d_name, "..")); + + while ((de = xreaddir(d))) { + assert(!streq(de->d_name, ".")); + assert(!streq(de->d_name, "..")); + + switch (de->d_type) { + DIR *dd; + int fd; + + case DT_REG: + if (level == 0 && streq(de->d_name, "sysrq-trigger")) { + f_reg_write(d, de->d_name, "h", 1); + } else if (level == 1 && streq(de->d_name, "clear_refs")) { + f_reg_write(d, de->d_name, "1", 1); + } else if (level == 3 && streq(de->d_name, "clear_refs")) { + f_reg_write(d, de->d_name, "1", 1); + } else { + f_reg(d, de->d_name); + } + break; + case DT_DIR: + fd = openat(dirfd(d), de->d_name, O_DIRECTORY|O_RDONLY); + if (fd == -1) + continue; + dd = fdopendir(fd); + if (!dd) + continue; + f(dd, level + 1); + closedir(dd); + break; + case DT_LNK: + f_lnk(d, de->d_name); + break; + default: + assert(0); + } + } +} + +int main(void) +{ + DIR *d; + + d = opendir("/proc"); + if (!d) + return 2; + f(d, 0); + return 0; +} |