On 17.03.2012 02:12, Paolo Bonzini wrote: [] >> While at it, add a unit-test file test-iov.c, >> to check various corner cases with iov_from_buf() >> and iov_to_buf() (all 3 functions uses exactly >> the same logic so iov_memset() should be covered >> too). >> >> Signed-off-by: Michael Tokarev <m...@tls.msk.ru> >> --- >> iov.c | 91 +++++++++++++++-------------------- >> iov.h | 12 ++++- >> test-iov.c | 158 >> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > > Makefile changes missing.
*sigh* Which changes? I'm sorry but i ran past any sane time limits for this long ago. Come on, which ANOTHER changes do you guys need for all this TRIVIAL stuff ??? Can you describe in a few words please? Thanks, /mjt > Also, please use g_test_rand_int_range to generate random numbers inside > GTester. The .xml output will include the seed so that failures are > reproducible. > > http://developer.gnome.org/glib/2.30/glib-Testing.html#g-test-rand-int > > Paolo > >> 3 files changed, 207 insertions(+), 54 deletions(-) >> >> diff --git a/iov.c b/iov.c >> index bc58cab..9657d28 100644 >> --- a/iov.c >> +++ b/iov.c >> @@ -7,6 +7,7 @@ >> * Author(s): >> * Anthony Liguori <aligu...@us.ibm.com> >> * Amit Shah <amit.s...@redhat.com> >> + * Michael Tokarev <m...@tls.msk.ru> >> * >> * This work is licensed under the terms of the GNU GPL, version 2. See >> * the COPYING file in the top-level directory. >> @@ -17,75 +18,61 @@ >> >> #include "iov.h" >> >> -size_t iov_from_buf(struct iovec *iov, unsigned int iov_cnt, size_t iov_off, >> - const void *buf, size_t size) >> +size_t iov_from_buf(struct iovec *iov, unsigned int iov_cnt, >> + size_t offset, const void *buf, size_t bytes) >> { >> - size_t iovec_off, buf_off; >> + size_t done; >> unsigned int i; >> - >> - iovec_off = 0; >> - buf_off = 0; >> - for (i = 0; i < iov_cnt && size; i++) { >> - if (iov_off < (iovec_off + iov[i].iov_len)) { >> - size_t len = MIN((iovec_off + iov[i].iov_len) - iov_off, size); >> - >> - memcpy(iov[i].iov_base + (iov_off - iovec_off), buf + buf_off, >> len); >> - >> - buf_off += len; >> - iov_off += len; >> - size -= len; >> + for (i = 0, done = 0; (offset || done < bytes) && i < iov_cnt; i++) { >> + if (offset < iov[i].iov_len) { >> + size_t len = MIN(iov[i].iov_len - offset, bytes - done); >> + memcpy(iov[i].iov_base + offset, buf + done, len); >> + done += len; >> + offset = 0; >> + } else { >> + offset -= iov[i].iov_len; >> } >> - iovec_off += iov[i].iov_len; >> } >> - return buf_off; >> + assert(offset == 0); >> + return done; >> } >> >> -size_t iov_to_buf(const struct iovec *iov, const unsigned int iov_cnt, >> size_t iov_off, >> - void *buf, size_t size) >> +size_t iov_to_buf(const struct iovec *iov, const unsigned int iov_cnt, >> + size_t offset, void *buf, size_t bytes) >> { >> - uint8_t *ptr; >> - size_t iovec_off, buf_off; >> + size_t done; >> unsigned int i; >> - >> - ptr = buf; >> - iovec_off = 0; >> - buf_off = 0; >> - for (i = 0; i < iov_cnt && size; i++) { >> - if (iov_off < (iovec_off + iov[i].iov_len)) { >> - size_t len = MIN((iovec_off + iov[i].iov_len) - iov_off , size); >> - >> - memcpy(ptr + buf_off, iov[i].iov_base + (iov_off - iovec_off), >> len); >> - >> - buf_off += len; >> - iov_off += len; >> - size -= len; >> + for (i = 0, done = 0; (offset || done < bytes) && i < iov_cnt; i++) { >> + if (offset < iov[i].iov_len) { >> + size_t len = MIN(iov[i].iov_len - offset, bytes - done); >> + memcpy(buf + done, iov[i].iov_base + offset, len); >> + done += len; >> + offset = 0; >> + } else { >> + offset -= iov[i].iov_len; >> } >> - iovec_off += iov[i].iov_len; >> } >> - return buf_off; >> + assert(offset == 0); >> + return done; >> } >> >> size_t iov_memset(const struct iovec *iov, const unsigned int iov_cnt, >> - size_t iov_off, int fillc, size_t size) >> + size_t offset, int fillc, size_t bytes) >> { >> - size_t iovec_off, buf_off; >> + size_t done; >> unsigned int i; >> - >> - iovec_off = 0; >> - buf_off = 0; >> - for (i = 0; i < iov_cnt && size; i++) { >> - if (iov_off < (iovec_off + iov[i].iov_len)) { >> - size_t len = MIN((iovec_off + iov[i].iov_len) - iov_off , size); >> - >> - memset(iov[i].iov_base + (iov_off - iovec_off), fillc, len); >> - >> - buf_off += len; >> - iov_off += len; >> - size -= len; >> + for (i = 0, done = 0; (offset || done < bytes) && i < iov_cnt; i++) { >> + if (offset < iov[i].iov_len) { >> + size_t len = MIN(iov[i].iov_len - offset, bytes - done); >> + memset(iov[i].iov_base + offset, fillc, len); >> + done += len; >> + offset = 0; >> + } else { >> + offset -= iov[i].iov_len; >> } >> - iovec_off += iov[i].iov_len; >> } >> - return buf_off; >> + assert(offset == 0); >> + return done; >> } >> >> size_t iov_size(const struct iovec *iov, const unsigned int iov_cnt) >> diff --git a/iov.h b/iov.h >> index 0b4acf4..19ee3b3 100644 >> --- a/iov.h >> +++ b/iov.h >> @@ -1,10 +1,11 @@ >> /* >> - * Helpers for getting linearized buffers from iov / filling buffers into >> iovs >> + * Helpers for using (partial) iovecs. >> * >> * Copyright (C) 2010 Red Hat, Inc. >> * >> * Author(s): >> * Amit Shah <amit.s...@redhat.com> >> + * Michael Tokarev <m...@tls.msk.ru> >> * >> * This work is licensed under the terms of the GNU GPL, version 2. See >> * the COPYING file in the top-level directory. >> @@ -28,6 +29,12 @@ size_t iov_size(const struct iovec *iov, const unsigned >> int iov_cnt); >> * only part of data will be copied, up to the end of the iovec. >> * Number of bytes actually copied will be returned, which is >> * min(bytes, iov_size(iov)-offset) >> + * `Offset' must point to the inside of iovec. >> + * It is okay to use very large value for `bytes' since we're >> + * limited by the size of the iovec anyway, provided that the >> + * buffer pointed to by buf has enough space. One possible >> + * such "large" value is -1 (sinice size_t is unsigned), >> + * so specifying `-1' as `bytes' means 'up to the end of iovec'. >> */ >> size_t iov_from_buf(struct iovec *iov, unsigned int iov_cnt, >> size_t offset, const void *buf, size_t bytes); >> @@ -37,11 +44,12 @@ size_t iov_to_buf(const struct iovec *iov, const >> unsigned int iov_cnt, >> /** >> * Set data bytes pointed out by iovec `iov' of size `iov_cnt' elements, >> * starting at byte offset `start', to value `fillc', repeating it >> - * `bytes' number of times. >> + * `bytes' number of times. `Offset' must point to the inside of iovec. >> * If `bytes' is large enough, only last bytes portion of iovec, >> * up to the end of it, will be filled with the specified value. >> * Function return actual number of bytes processed, which is >> * min(size, iov_size(iov) - offset). >> + * Again, it is okay to use large value for `bytes' to mean "up to the end". >> */ >> size_t iov_memset(const struct iovec *iov, const unsigned int iov_cnt, >> size_t offset, int fillc, size_t bytes); >> diff --git a/test-iov.c b/test-iov.c >> new file mode 100644 >> index 0000000..fd8f9fe >> --- /dev/null >> +++ b/test-iov.c >> @@ -0,0 +1,158 @@ >> +#include <glib.h> >> +#include "qemu-common.h" >> +#include "iov.h" >> + >> +/* return a (pseudo-)random number in [min, max] range */ >> + >> +static inline int rannum(int min, int max) >> +{ >> + return min + random() % (max - min + 1); >> +} >> + >> +/* create a randomly-sized iovec with random vectors */ >> +static void iov_random(struct iovec **iovp, unsigned *iov_cntp) >> +{ >> + unsigned niov = rannum(3, 8); >> + struct iovec *iov = g_malloc(niov * sizeof(*iov)); >> + unsigned i; >> + for (i = 0; i < niov; ++i) { >> + iov[i].iov_len = rannum(2, 10); >> + iov[i].iov_base = g_malloc(iov[i].iov_len); >> + } >> + *iovp = iov; >> + *iov_cntp = niov; >> +} >> + >> +static void iov_free(struct iovec *iov, unsigned niov) >> +{ >> + unsigned i; >> + for (i = 0; i < niov; ++i) { >> + g_free(iov[i].iov_base); >> + } >> + g_free(iov); >> +} >> + >> +static void test_iov_bytes(struct iovec *iov, unsigned niov, >> + size_t offset, size_t bytes) >> +{ >> + unsigned i; >> + size_t j, o; >> + unsigned char *b; >> + o = 0; >> + >> + /* we walk over all elements, */ >> + for (i = 0; i < niov; ++i) { >> + b = iov[i].iov_base; >> + /* over each char of each element, */ >> + for (j = 0; j < iov[i].iov_len; ++j) { >> + /* counting each of them and >> + * verifying that the ones within [offset,offset+bytes) >> + * range are equal to the position number (o) */ >> + if (o >= offset && o < offset + bytes) { >> + g_assert(b[j] == (o & 255)); >> + } >> + ++o; >> + } >> + } >> +} >> + >> +static void test_to_from_buf_1(void) >> +{ >> + struct iovec *iov; >> + unsigned niov; >> + size_t sz; >> + unsigned char *ibuf, *obuf; >> + unsigned i, j, n; >> + >> + iov_random(&iov, &niov); >> + sz = iov_size(iov, niov); >> + >> + ibuf = g_malloc(sz + 8) + 4; >> + memcpy(ibuf-4, "aaaa", 4); memcpy(ibuf + sz, "bbbb", 4); >> + obuf = g_malloc(sz + 8) + 4; >> + memcpy(obuf-4, "xxxx", 4); memcpy(obuf + sz, "yyyy", 4); >> + >> + /* fill in ibuf with 0123456... */ >> + for (i = 0; i < sz; ++i) { >> + ibuf[i] = i & 255; >> + } >> + >> + for (i = 0; i <= sz; ++i) { >> + >> + /* Test from/to buf for offset(i) in [0..sz] up to the end of >> buffer. >> + * For last iteration with offset == sz, the procedure should >> + * skip whole vector and process exactly 0 bytes */ >> + >> + /* first set bytes [i..sz) to some "random" value */ >> + n = iov_memset(iov, niov, 0, i&255, -1); >> + g_assert(n == sz); >> + >> + /* next copy bytes [i..sz) from ibuf to iovec */ >> + n = iov_from_buf(iov, niov, i, ibuf + i, -1); >> + g_assert(n == sz - i); >> + >> + /* clear part of obuf */ >> + memset(obuf + i, 0, sz - i); >> + /* and set this part of obuf to values from iovec */ >> + n = iov_to_buf(iov, niov, i, obuf + i, -1); >> + g_assert(n == sz - i); >> + >> + /* now compare resulting buffers */ >> + g_assert(memcmp(ibuf, obuf, sz) == 0); >> + >> + /* test just one char */ >> + n = iov_to_buf(iov, niov, i, obuf + i, 1); >> + g_assert(n == (i < sz)); >> + if (n) { >> + g_assert(obuf[i] == (i & 255)); >> + } >> + >> + for (j = i; j <= sz; ++j) { >> + /* now test num of bytes cap up to byte no. j, >> + * with j in [i..sz]. */ >> + >> + /* clear iovec */ >> + n = iov_memset(iov, niov, 0, j&255, -1); >> + g_assert(n == sz); >> + >> + /* copy bytes [i..j) from ibuf to iovec */ >> + n = iov_from_buf(iov, niov, i, ibuf + i, j - i); >> + g_assert(n == j - i); >> + >> + /* clear part of obuf */ >> + memset(obuf + i, 0, j - i); >> + >> + /* copy bytes [i..j) from iovec to obuf */ >> + n = iov_to_buf(iov, niov, i, obuf + i, j - i); >> + g_assert(n == j - i); >> + >> + /* verify result */ >> + g_assert(memcmp(ibuf, obuf, sz) == 0); >> + >> + /* now actually check if the iovec contains the right data */ >> + test_iov_bytes(iov, niov, i, j - i); >> + } >> + } >> + g_assert(!memcmp(ibuf-4, "aaaa", 4) && !memcmp(ibuf+sz, "bbbb", 4)); >> + g_free(ibuf-4); >> + g_assert(!memcmp(obuf-4, "xxxx", 4) && !memcmp(obuf+sz, "yyyy", 4)); >> + g_free(obuf-4); >> + iov_free(iov, niov); >> +} >> + >> +static void test_to_from_buf(void) >> +{ >> + int x; >> + /* repeat it several times with different (random) values */ >> + for (x = 0; x < 4; ++x) { >> + test_to_from_buf_1(); >> + } >> +} >> + >> +int main(int argc, char **argv) >> +{ >> + srandom(getpid()); >> + g_test_init(&argc, &argv, NULL); >> + g_test_add_func("/basic/iov/from-to-buf", test_to_from_buf); >> + return g_test_run(); >> +} >
