[ccan] [PATCH] rszshm: New module
Dan Good
dan at dancancode.com
Tue Jan 19 17:04:02 AEDT 2016
rszshm - resizable pointer-safe shared memory
Signed-off-by: Dan Good <dan at dancancode.com>
---
Makefile-ccan | 1 +
ccan/rszshm/LICENSE | 1 +
ccan/rszshm/_info | 96 ++++++++++++++++
ccan/rszshm/rszshm.c | 240 +++++++++++++++++++++++++++++++++++++++
ccan/rszshm/rszshm.h | 301 +++++++++++++++++++++++++++++++++++++++++++++++++
ccan/rszshm/test/run.c | 194 +++++++++++++++++++++++++++++++
6 files changed, 833 insertions(+)
create mode 120000 ccan/rszshm/LICENSE
create mode 100644 ccan/rszshm/_info
create mode 100644 ccan/rszshm/rszshm.c
create mode 100644 ccan/rszshm/rszshm.h
create mode 100644 ccan/rszshm/test/run.c
diff --git a/Makefile-ccan b/Makefile-ccan
index 8d99bbf..9469334 100644
--- a/Makefile-ccan
+++ b/Makefile-ccan
@@ -100,6 +100,7 @@ MODS_WITH_SRC := aga \
rbuf \
read_write_all \
rfc822 \
+ rszshm \
siphash \
sparse_bsearch \
str \
diff --git a/ccan/rszshm/LICENSE b/ccan/rszshm/LICENSE
new file mode 120000
index 0000000..4f8ee74
--- /dev/null
+++ b/ccan/rszshm/LICENSE
@@ -0,0 +1 @@
+../../licenses/APACHE-2
\ No newline at end of file
diff --git a/ccan/rszshm/_info b/ccan/rszshm/_info
new file mode 100644
index 0000000..2134e67
--- /dev/null
+++ b/ccan/rszshm/_info
@@ -0,0 +1,96 @@
+#include "config.h"
+#include <stdio.h>
+#include <string.h>
+
+/**
+ * rszshm - resizable pointer-safe shared memory
+ *
+ * If two separate processes have shared mappings of the same file at the
+ * same address, then pointers to addresses within the region can be shared
+ * between the processes and safely dereferenced.
+ *
+ * Mapping to the same address in unrelated processes is nontrivial. One can
+ * request a specific address, but mmap will return another in case of an
+ * overlap. One can require a specific address, but mmap will unmap anything
+ * overlapped. On Linux boxes it can be seen that the used addresses clump
+ * at either end of the address range. rszshm tries to mmap in the middle
+ * of the address range, and checks if the requested address matches the
+ * returned address. If not, additional addresses are tried. Once mapped,
+ * the address is recorded to a header in the file. Another process reads the
+ * header and requests the saved address from mmap. If the returned address
+ * matches, work proceeds. While the defaults provide a propitious search,
+ * all the search parameters may be specified.
+ *
+ * To accommodate resizing, rszshm first maps a large, private, noreserve map.
+ * This serves to claim a span of addresses. The shared file mapping then
+ * overlays the beginning of the span. Later calls to extend the mapping
+ * overlay more of the span. Attempts to extend beyond the end of the span
+ * return an error.
+ *
+ * Example:
+ * // fork x times, grow and fill shared memory cooperatively
+ * #include <assert.h>
+ * #include <err.h>
+ * #include <signal.h>
+ * #include <stdio.h>
+ * #include <unistd.h>
+ * #include <ccan/rszshm/rszshm.h>
+ *
+ * #define ok(x) ({ int n = (x); if (n == -1) err(1, "%s", #x); n; })
+ *
+ * int main(int argc, char *argv[]) {
+ * int pidcnt, stopval, n, i;
+ * struct rszshm *r;
+ * char *m;
+ *
+ * assert(argc == 3);
+ * pidcnt = atoi(argv[1]);
+ * stopval = atoi(argv[2]);
+ * assert(pidcnt > 0 && stopval > 0);
+ *
+ * if (!rszshm_mkm(r, 4096, NULL))
+ * err(1, "rszshm_mkm");
+ *
+ * printf("%s\n", r->fname);
+ *
+ * for (n = 0; n < pidcnt - 1; n++)
+ * if (ok(fork()) == 0)
+ * break;
+ *
+ * m = (char *) r->dat + sizeof(int);
+ * #define next() (__sync_fetch_and_add((int *) r->dat, 1))
+ *
+ * for(i = next(); i < stopval; i = next()) {
+ * if (i >= r->cap - sizeof(int))
+ * ok(rszshm_grow(r));
+ * assert(m[i] == '\0');
+ * m[i] = 'A' + n;
+ * kill(0, 0); // busy work
+ * }
+ *
+ * rszshm_free(r);
+ * return 0;
+ * }
+ * // $ ./foo 8 $((4*1024*1024-28))
+ * // /dev/shm/rszshm_LAsEvt/0
+ * // $ tail -c +29 /dev/shm/rszshm_LAsEvt/0 | sed 's/./&\n/g' | sort | uniq -c | tr '\n' '\t'; echo
+ * // 515532 A 527251 B 512930 C 513062 D 544326 E 545876 F 512936 G 522363 H
+ *
+ * License: APACHE-2
+ * Author: Dan Good <dan at dancancode.com>
+ *
+ * Ccanlint:
+ * // tests use optional macros containing statement expressions
+ * tests_compile_without_features FAIL
+ */
+int main(int argc, char *argv[])
+{
+ /* Expect exactly one argument */
+ if (argc != 2)
+ return 1;
+
+ if (strcmp(argv[1], "depends") == 0)
+ return 0;
+
+ return 1;
+}
diff --git a/ccan/rszshm/rszshm.c b/ccan/rszshm/rszshm.c
new file mode 100644
index 0000000..32db455
--- /dev/null
+++ b/ccan/rszshm/rszshm.c
@@ -0,0 +1,240 @@
+/* Licensed under Apache License v2.0 - see LICENSE file for details */
+#include "config.h"
+#include "rszshm.h"
+
+#define _XOPEN_SOURCE 700
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <sys/file.h>
+
+#define pgup(x, pgsz) (((x) + (pgsz) - 1) & ~((pgsz) - 1))
+
+void *rszshm_mk(struct rszshm *r, size_t flen, const char *fname, struct rszshm_scan scan)
+{
+ long pgsz = sysconf(_SC_PAGE_SIZE);
+ int i, errno_;
+ char *m, *tgt, *p = NULL;
+
+ if (!r || flen == 0 || scan.len < flen + sizeof(*r->hdr) ||
+ !scan.start || scan.len == 0 || scan.hop == 0 || scan.iter == 0 ||
+ (fname && strnlen(fname, RSZSHM_PATH_MAX) == RSZSHM_PATH_MAX)) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ *r = (typeof(*r)) { -1, 0, "", NULL, NULL };
+ strcpy(r->fname, fname ? fname : RSZSHM_DFLT_FNAME);
+
+ flen = pgup(flen + sizeof(*r->hdr), pgsz);
+ scan.len = pgup(scan.len, pgsz);
+
+ for (i = 1, tgt = scan.start; i <= scan.iter; i++) {
+ m = mmap(tgt, scan.len, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON|MAP_NORESERVE, -1, 0);
+ if (m == MAP_FAILED)
+ return NULL;
+ if (m == tgt)
+ break;
+ munmap(m, scan.len);
+ m = NULL;
+ tgt += (i % 2 == 0 ? 1 : -1) * i * scan.hop;
+ }
+ if (!m) {
+ errno = ENOSPC;
+ return NULL;
+ }
+
+ if ((p = strstr(r->fname, "XXXXXX/")) != NULL) {
+ p += 6;
+ *p = '\0';
+ if (!mkdtemp(r->fname))
+ goto err;
+ *p = '/';
+ }
+
+ if ((r->fd = open(r->fname, O_CREAT|O_EXCL|O_RDWR, p ? 0600 : 0666)) == -1)
+ goto err;
+
+ if (ftruncate(r->fd, flen) == -1)
+ goto err;
+
+ if (mmap(m, flen, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_FIXED, r->fd, 0) == MAP_FAILED)
+ goto err;
+
+ *(r->hdr = (typeof(r->hdr)) m) = (typeof(*r->hdr)) { flen, scan.len, m };
+
+ if (msync(m, sizeof(*r->hdr), MS_SYNC) == -1)
+ goto err;
+
+ r->flen = flen;
+ r->cap = flen - sizeof(*r->hdr);
+ r->dat = m + sizeof(*r->hdr);
+
+ return r->dat;
+
+err:
+ errno_ = errno;
+ if (m && m != MAP_FAILED)
+ munmap(m, scan.len);
+ if (r->fd != -1) {
+ close(r->fd);
+ unlink(r->fname);
+ }
+ if (p) {
+ *p = '\0';
+ rmdir(r->fname);
+ *p = '/';
+ }
+ errno = errno_;
+ return NULL;
+}
+
+void *rszshm_at(struct rszshm *r, const char *fname)
+{
+ struct rszshm_hdr h;
+ int fd = -1, ret, errno_;
+ char *m = NULL;
+
+ if (!r || !fname || !fname[0] ||
+ strnlen(fname, RSZSHM_PATH_MAX) == RSZSHM_PATH_MAX) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ if ((fd = open(fname, O_RDWR)) == -1)
+ return NULL;
+
+ if ((ret = read(fd, &h, sizeof(h))) == -1)
+ goto err;
+
+ if (ret != sizeof(h) || !h.addr || h.flen == 0 || h.max == 0) {
+ errno = ENODATA;
+ goto err;
+ }
+
+ m = mmap(h.addr, h.max, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON|MAP_NORESERVE, -1, 0);
+ if (m == MAP_FAILED)
+ goto err;
+ if (m != h.addr) {
+ errno = ENOSPC;
+ goto err;
+ }
+
+ if (mmap(m, h.flen, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_FIXED, fd, 0) == MAP_FAILED)
+ goto err;
+
+ *r = (typeof(*r)) { .fd = fd, .flen = h.flen, .hdr = (typeof(r->hdr)) m,
+ .dat = m + sizeof(h), .cap = h.flen - sizeof(h) };
+ strcpy(r->fname, fname);
+
+ return r->dat;
+
+err:
+ errno_ = errno;
+ if (m && m != MAP_FAILED)
+ munmap(m, h.max);
+ close(fd);
+ errno = errno_;
+ return NULL;
+}
+
+#undef rszshm_up
+int rszshm_up(struct rszshm *r)
+{
+ size_t flen;
+
+ assert(r);
+
+ flen = r->hdr->flen;
+ if (r->flen == flen)
+ return 0;
+ if (mmap(r->hdr, flen, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_FIXED, r->fd, 0) == MAP_FAILED)
+ return -1;
+
+ r->flen = flen;
+ r->cap = flen - sizeof(*r->hdr);
+ return 1;
+}
+
+int rszshm_grow(struct rszshm *r)
+{
+ int ret;
+ assert(r);
+
+ if ((ret = rszshm_up(r)) != 0)
+ return ret;
+
+ if (r->flen == r->hdr->max) {
+ errno = ENOMEM;
+ return -1;
+ }
+
+ if (flock(r->fd, LOCK_EX) == -1)
+ return -1;
+
+ if ((ret = rszshm_up(r)) == 0) {
+ int flen = r->hdr->flen * 2 < r->hdr->max ? r->hdr->flen * 2 : r->hdr->max;
+
+ if (ftruncate(r->fd, flen) != -1 &&
+ mmap(r->hdr, flen, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_FIXED, r->fd, 0) != MAP_FAILED) {
+ r->flen = r->hdr->flen = flen;
+ r->cap = flen - sizeof(*r->hdr);
+ ret = 1;
+ }
+ else
+ ret = -1;
+ }
+
+ flock(r->fd, LOCK_UN);
+ return ret;
+}
+
+int rszshm_dt(struct rszshm *r)
+{
+ int ret[3];
+ assert(r);
+
+ /* ok to call twice, since free macro calls this */
+ if (r->fd == -1)
+ return 0;
+
+ ret[0] = msync(r->hdr, r->flen, MS_SYNC);
+ ret[1] = munmap(r->hdr, r->hdr->max);
+ ret[2] = close(r->fd);
+
+ r->fd = -1;
+ r->flen = 0;
+ r->hdr = NULL;
+ r->dat = NULL;
+ r->cap = 0;
+
+ return ret[0] == 0 && ret[1] == 0 && ret[2] == 0 ? 0 : -1;
+}
+
+int rszshm_unlink(struct rszshm *r)
+{
+ assert(r);
+ return unlink(r->fname);
+}
+
+int rszshm_rmdir(struct rszshm *r)
+{
+ int ret;
+ char *p;
+
+ assert(r);
+
+ if ((p = strrchr(r->fname, '/')) == NULL) {
+ errno = ENOTDIR;
+ return -1;
+ }
+
+ *p = '\0';
+ ret = rmdir(r->fname);
+ *p = '/';
+ return ret;
+}
diff --git a/ccan/rszshm/rszshm.h b/ccan/rszshm/rszshm.h
new file mode 100644
index 0000000..c29e4a5
--- /dev/null
+++ b/ccan/rszshm/rszshm.h
@@ -0,0 +1,301 @@
+/* Licensed under Apache License v2.0 - see LICENSE file for details */
+#ifndef CCAN_RSZSHM_H
+#define CCAN_RSZSHM_H
+#include "config.h"
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+/**
+ * struct rszshm_scan - parameters for the free region search
+ * @start: first address to test
+ * @len: size of region to test
+ * @hop: offset of the next test
+ * @iter: number of attempts
+ *
+ * See rszshm_mk for search details.
+ */
+struct rszshm_scan {
+ void *start;
+ size_t len;
+ size_t hop;
+ unsigned iter;
+};
+
+#define KiB (1024UL)
+#define MiB (KiB*KiB)
+#define GiB (MiB*KiB)
+#ifdef __x86_64__
+#define TiB (GiB*KiB)
+#define RSZSHM_DFLT_SCAN (struct rszshm_scan) { (void *) (64*TiB), 4*GiB, 1*TiB, 10 }
+#else
+#define RSZSHM_DFLT_SCAN (struct rszshm_scan) { (void *) ((1024+512)*MiB), 256*MiB, 256*MiB, 10 }
+#endif
+
+/**
+ * struct rszshm_hdr - header describing mapped memory
+ * @flen: length of the shared file mapping
+ * @max: length of the private mapping
+ * @addr: address of the mapping
+ *
+ * The shared region is mapped over the private region.
+ * max is the maximum size the shared region can be extended.
+ * addr and max are set at creation time and do not change.
+ * flen is updated each time the file and shared region is grown.
+ */
+struct rszshm_hdr {
+ size_t flen;
+ size_t max;
+ void *addr;
+};
+
+/**
+ * struct rszshm - handle for a mapped region
+ * @fd: file descriptor of the mapped file
+ * @flen: length of the mapped shared file in this process
+ * @fname: path of the mapped file
+ * @hdr: pointer to the mapped region header
+ * @dat: pointer to the usable space after the header
+ * @cap: length of the usable space after the header
+ *
+ * flen is updated by rszshm_grow, or by rszshm_up.
+ */
+#define RSZSHM_PATH_MAX 128
+#define RSZSHM_DFLT_FNAME "/dev/shm/rszshm_XXXXXX/0"
+struct rszshm {
+ int fd;
+ size_t flen;
+ char fname[RSZSHM_PATH_MAX];
+ struct rszshm_hdr *hdr;
+ void *dat;
+ size_t cap;
+};
+
+/**
+ * rszshm_mk - make and mmap a shareable region
+ * @r: pointer to handle
+ * @flen: initial length of shared mapping
+ * @fname: path to file to be created, may be NULL or contain template
+ * @scan: struct specifying search parameters
+ *
+ * The handle pointed to by r is populated by rszshm_mk. flen is increased
+ * by the size of struct rszshm_hdr and rounded up to the next multiple of
+ * page size. If the directory portion of fname ends with XXXXXX, mkdtemp(3)
+ * is used. If fname is NULL, a default path with template is used.
+ *
+ * If rszshm_mk is called with only three arguments, a default scan struct
+ * is used. To supply a struct via compound literal, wrap the argument in
+ * parenthesis to avoid macro failure.
+ *
+ * rszshm_mk attempts to mmap a region of scan.len size at scan.start address.
+ * This is a private anonymous noreserve map used to claim an address space.
+ * If the mapping returns a different address, the region is unmapped, and
+ * another attempt is made at scan.start - scan.hop. If necessary, the next
+ * address tried is scan.start + scan.hop, then scan.start - (2 * scan.hop),
+ * and so on for at most scan.iter iterations. The pattern can be visualized
+ * as a counterclockwise spiral. If no match is found, NULL is returned and
+ * errno is set to ENOSPC.
+ *
+ * When an mmap returns an address matching the requested address, that region
+ * is used. If fname contains a template, mkdtemp(3) is called. A file is
+ * created, and extended to flen bytes. It must not already exist. This file
+ * is mmap'd over the region using MAP_FIXED. The mapping may later be extended
+ * by rszshm_grow consuming more of the claimed address space.
+ *
+ * The initial portion of the mapped file is populated with a struct rszshm_hdr,
+ * and msync called to write out the header.
+ *
+ * Example:
+ * struct rszshm r, s, t;
+ *
+ * if (!rszshm_mk(&r, 4*MiB, NULL))
+ * err(1, "rszshm_mk");
+ * // map at 0x400000000000
+ *
+ * if (!rszshm_mk(&s, 4*MiB, "/var/tmp/dat"))
+ * err(1, "rszshm_mk");
+ * // map at 0x3f0000000000
+ *
+ * if (!rszshm_mk(&t, 4*MiB, NULL, ((struct rszshm_scan) { (void *) (48*TiB), 4*GiB, 1*TiB, 10 })))
+ * err(1, "rszshm_mk");
+ * // map at 0x300000000000
+ *
+ * Returns: r->dat address on success, NULL on error
+ */
+void *rszshm_mk(struct rszshm *r, size_t flen, const char *fname, struct rszshm_scan scan);
+#define __4args(a,b,c,d,...) a, b, c, d
+#define rszshm_mk(...) rszshm_mk(__4args(__VA_ARGS__, RSZSHM_DFLT_SCAN))
+
+#if HAVE_STATEMENT_EXPR
+/**
+ * rszshm_mkm - malloc handle and run rszshm_mk
+ * @r: pointer to handle
+ * @flen: initial length of shared mapping
+ * @fname: path to file to be created, may be NULL or contain template
+ *
+ * Example:
+ * struct rszshm *r;
+ *
+ * if (!rszshm_mkm(r, 4*MiB, NULL))
+ * err(1, "rszshm_mkm");
+ *
+ * Returns: result of rszshm_mk
+ */
+#define rszshm_mkm(r, fl, fn) ({ \
+ void *__p = NULL; \
+ r = malloc(sizeof(*r)); \
+ if (r && !(__p = rszshm_mk(r, fl, fn))) { \
+ free(r); \
+ r = 0; \
+ } \
+ __p; \
+})
+#endif
+
+/**
+ * rszshm_at - mmap ("attach") an existing shared region
+ * @r: pointer to handle
+ * @fname: path to file
+ *
+ * rszshm_at lets unrelated processes attach an existing shared region.
+ * fname must name a file previously created by rszshm_mk in another process.
+ * Note, fork'd children of the creating process inherit the mapping and
+ * should *not* call rszshm_at.
+ *
+ * rszshm_at opens and reads the header from the file. It makes a private
+ * anonymous noreserve mapping at the address recorded in the header.
+ * If mmap returns an address other than the requested one, munmap
+ * is called, errno is set to ENOSPC, and NULL is returned.
+ *
+ * Once the address space is claimed, the file is mmap'd over the region
+ * using MAP_FIXED. The remaining claimed address space will be used by
+ * later calls to rszshm_grow. Finally, the handle is populated and r->dat
+ * returned.
+ *
+ * Example:
+ * struct rszshm r;
+ *
+ * if (!rszshm_at(&r, "/dev/shm/rszshm_LAsEvt/0"))
+ * err(1, "rszshm_at");
+ *
+ * Returns: r->dat address on success, NULL on error
+ */
+void *rszshm_at(struct rszshm *r, const char *fname);
+
+#if HAVE_STATEMENT_EXPR
+/**
+ * rszshm_atm - malloc handle and run rszshm_at
+ * @r: pointer to handle
+ * @fname: path to file
+ *
+ * Example:
+ * struct rszshm *r;
+ *
+ * if (!rszshm_atm(r, "/dev/shm/rszshm_LAsEvt/0"))
+ * err(1, "rszshm_atm");
+ *
+ * Returns: result of rszshm_at
+ */
+#define rszshm_atm(r, f) ({ \
+ void *__p = NULL; \
+ r = malloc(sizeof(*r)); \
+ if (r && !(__p = rszshm_at(r, f))) { \
+ free(r); \
+ r = 0; \
+ } \
+ __p; \
+})
+#endif
+
+/**
+ * rszshm_dt - unmap ("detach") shared region
+ * @r: pointer to handle
+ *
+ * Calls msync, munmap, and close. Resets handle values except fname.
+ * (fname is used by rszshm_rm*.)
+ *
+ * Returns: 0 on success, -1 if any call failed
+ */
+int rszshm_dt(struct rszshm *r);
+
+/**
+ * rszshm_up - update mapping of shared region
+ * @r: pointer to handle
+ *
+ * Check if flen from the region header matches flen from the handle.
+ * They will diverge when another process runs rszshm_grow.
+ * If they are different, call mmap with the header flen and MAP_FIXED,
+ * and update handle.
+ *
+ * Returns: -1 if mmap fails, 0 for no change, 1 is mapping updated
+ */
+int rszshm_up(struct rszshm *r);
+#define rszshm_up(r) (assert(r), (r)->flen == (r)->hdr->flen ? 0 : rszshm_up(r))
+
+/**
+ * rszshm_grow - double the shared region, conditionally
+ * @r: pointer to handle
+ *
+ * If the region is already at capacity, set errno to ENOMEM, and return -1.
+ *
+ * rszshm_up is called, to see if another process has already grown the region.
+ * If not, a lock is acquired and the check repeated, to avoid races.
+ * The file is extended, and mmap called with MAP_FIXED. The header and handle
+ * are updated.
+ *
+ * Returns: 1 on success, -1 on error
+ */
+int rszshm_grow(struct rszshm *r);
+
+/**
+ * rszshm_unlink - unlink shared file
+ * @r: pointer to handle
+ *
+ * Returns: result of unlink
+ */
+int rszshm_unlink(struct rszshm *r);
+
+/**
+ * rszshm_rmdir - rmdir of fname directory
+ * @r: pointer to handle
+ *
+ * Returns: result of rmdir
+ */
+int rszshm_rmdir(struct rszshm *r);
+
+#if HAVE_STATEMENT_EXPR
+/**
+ * rszshm_rm - remove file and directory
+ * @r: pointer to handle
+ *
+ * Calls rszshm_unlink and rszshm_rmdir.
+ *
+ * Returns: 0 on success, -1 on error
+ */
+#define rszshm_rm(r) ({ \
+ int __ret; \
+ assert(r); \
+ __ret = rszshm_unlink(r); \
+ if (__ret == 0) \
+ __ret = rszshm_rmdir(r); \
+ __ret; \
+})
+#endif
+
+#if HAVE_STATEMENT_EXPR
+/**
+ * rszshm_free - run rszshm_dt and free malloced handle
+ * @r: pointer to handle
+ *
+ * Returns: result of rszshm_dt
+ */
+#define rszshm_free(r) ({ \
+ int __i = rszshm_dt(r); \
+ free(r); \
+ r = 0; \
+ __i; \
+})
+#endif
+
+#endif
diff --git a/ccan/rszshm/test/run.c b/ccan/rszshm/test/run.c
new file mode 100644
index 0000000..718af7a
--- /dev/null
+++ b/ccan/rszshm/test/run.c
@@ -0,0 +1,194 @@
+#define _GNU_SOURCE
+#include <err.h>
+#include <setjmp.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include <ccan/rszshm/rszshm.h>
+#include <ccan/tap/tap.h>
+
+#include <sys/mman.h>
+#include <sys/file.h>
+
+int fail_close, fail_flock, fail_ftruncate, fail_msync, fail_munmap, fail_open;
+#define close(...) (fail_close ? errno = 9000, -1 : close(__VA_ARGS__))
+#define flock(...) (fail_flock ? errno = 9001, -1 : flock(__VA_ARGS__))
+#define ftruncate(...) (fail_ftruncate ? errno = 9002, -1 : ftruncate(__VA_ARGS__))
+#define msync(...) (fail_msync ? errno = 9003, -1 : msync(__VA_ARGS__))
+#define munmap(...) (fail_munmap ? errno = 9004, -1 : munmap(__VA_ARGS__))
+#define open(...) (fail_open ? errno = 9005, -1 : open(__VA_ARGS__))
+
+int fail_read, short_read;
+#define read(...) (fail_read ? errno = 9006, -1 : short_read ? 1 : read(__VA_ARGS__))
+
+int fail_mmap_anon, fail_mmap_fixed, bad_mmap_addr;
+#define mmap(adr, len, rw, flags, fd, off) ( \
+ fail_mmap_anon && (flags) & MAP_ANON ? errno = 9010, MAP_FAILED : \
+ fail_mmap_fixed && (flags) & MAP_FIXED ? errno = 9011, MAP_FAILED : \
+ bad_mmap_addr ? NULL : \
+ mmap(adr, len, rw, flags, fd, off) \
+)
+#include <ccan/rszshm/rszshm.c>
+
+#define noerr(x) ({ int n = (x); if (n == -1) err(1, "%s", #x); n; })
+
+#define longstr \
+".................................................................................................................................."
+
+static jmp_buf j;
+static struct sigaction sa;
+static void segvjmp(int signum)
+{
+ longjmp(j, 1);
+}
+
+int main(void)
+{
+ plan_tests(37);
+
+ ok1(rszshm_mk(NULL, 0, NULL) == NULL && errno == EINVAL);
+
+ struct rszshm s, t;
+ ok1(rszshm_mk(&s, 0, NULL) == NULL && errno == EINVAL);
+
+ ok1(rszshm_mk(&s, 4096, longstr) == NULL && errno == EINVAL);
+
+ fail_mmap_anon = 1;
+ ok1(rszshm_mk(&s, 4096, NULL) == NULL && errno == 9010);
+ rszshm_rm(&s);
+ fail_mmap_anon = 0;
+
+ fail_open = 1;
+ ok1(rszshm_mk(&s, 4096, NULL) == NULL && errno == 9005);
+ rszshm_rm(&s);
+ fail_open = 0;
+
+ fail_ftruncate = 1;
+ ok1(rszshm_mk(&s, 4096, NULL) == NULL && errno == 9002);
+ rszshm_rm(&s);
+ fail_ftruncate = 0;
+
+ fail_mmap_fixed = 1;
+ ok1(rszshm_mk(&s, 4096, NULL) == NULL && errno == 9011);
+ rszshm_rm(&s);
+ fail_mmap_fixed = 0;
+
+ fail_msync = 1;
+ ok1(rszshm_mk(&s, 4096, NULL) == NULL && errno == 9003);
+ rszshm_rm(&s);
+ fail_msync = 0;
+
+ ok1(rszshm_mk(&s, 4096, NULL) != NULL);
+
+ struct rszshm_scan scan = RSZSHM_DFLT_SCAN;
+ scan.iter = 1;
+ ok1(rszshm_mk(&t, 4096, NULL, scan) == NULL && errno == ENOSPC);
+
+ ok1(rszshm_dt(&s) == 0);
+ ok1(rszshm_rm(&s) == 0);
+
+ long pgsz = sysconf(_SC_PAGE_SIZE);
+ scan.len = UINT64_MAX - pgsz;
+ ok1(rszshm_mk(&t, 4096, NULL, scan) == NULL && errno == ENOMEM);
+
+ ok1(rszshm_mk(&t, 4096, "foo/bar_XXXXXX/0") == NULL && errno == ENOENT);
+
+ struct rszshm *r;
+ ok1(rszshm_mkm(r, 4096, NULL) != NULL);
+
+ pid_t p, *pp;
+ noerr(p = fork());
+ char *fname = strdupa(r->fname);
+ if (p)
+ waitpid(p, NULL, 0);
+ else {
+ ok1(rszshm_free(r) == 0);
+
+ struct rszshm *q;
+ ok1(rszshm_atm(q, fname) != NULL);
+
+ *((pid_t *) q->dat) = getpid();
+
+ ok1(rszshm_up(q) == 0);
+ ok1(rszshm_grow(q) == 1);
+ ok1(rszshm_free(q) == 0);
+ exit(0);
+ }
+ pp = (pid_t *) r->dat;
+ ok1(p == *pp);
+
+ fail_mmap_fixed = 1;
+ ok1(rszshm_up(r) == -1 && errno == 9011);
+ fail_mmap_fixed = 0;
+
+ ok1(rszshm_grow(r) == 1);
+
+ ok1(rszshm_dt(r) == 0);
+
+ sa.sa_handler = segvjmp;
+ sa.sa_flags = SA_RESETHAND;
+ sigemptyset(&sa.sa_mask);
+ sigaction(SIGSEGV, &sa, NULL);
+ if (setjmp(j) == 0)
+ fail("still mapped after detach: %d", *pp);
+ else
+ pass("access after detach gives segv, OK!");
+
+ ok1(rszshm_at(r, longstr) == NULL && errno == EINVAL);
+
+ fail_open = 1;
+ ok1(rszshm_at(r, fname) == NULL && errno == 9005);
+ fail_open = 0;
+
+ fail_read = 1;
+ ok1(rszshm_at(r, fname) == NULL && errno == 9006);
+ fail_read = 0;
+
+ short_read = 1;
+ ok1(rszshm_at(r, fname) == NULL && errno == ENODATA);
+ short_read = 0;
+
+ fail_mmap_anon = 1;
+ ok1(rszshm_at(r, fname) == NULL && errno == 9010);
+ fail_mmap_anon = 0;
+
+ bad_mmap_addr = 1;
+ ok1(rszshm_at(r, fname) == NULL && errno == ENOSPC);
+ bad_mmap_addr = 0;
+
+ fail_mmap_fixed = 1;
+ ok1(rszshm_at(r, fname) == NULL && errno == 9011);
+ fail_mmap_fixed = 0;
+
+ ok1(rszshm_at(r, fname) != NULL);
+ ok1(p == *pp);
+
+ struct rszshm_hdr save = *r->hdr;
+ r->hdr->flen = r->flen;
+ r->hdr->max = r->flen;
+ ok1(rszshm_grow(r) == -1 && errno == ENOMEM);
+ *r->hdr = save;
+
+ fail_flock = 1;
+ ok1(rszshm_grow(r) == -1 && errno == 9001);
+ fail_flock = 0;
+
+ fail_ftruncate = 1;
+ ok1(rszshm_grow(r) == -1 && errno == 9002);
+ fail_ftruncate = 0;
+
+ ok1(rszshm_grow(r) == 1);
+ ok1(rszshm_dt(r) == 0);
+ ok1(rszshm_rm(r) == 0);
+
+ r->fname[0] = '\0';
+ ok1(rszshm_rmdir(r) == -1 && errno == ENOTDIR);
+
+ ok1(rszshm_free(r) == 0);
+
+ return exit_status();
+}
--
2.4.3
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