Add alloc_size(): every allocator has to be able to answer this, since

free() doesn't have a size arg.

diff --git a/ccan/alloc/alloc.c b/ccan/alloc/alloc.c
index f7a05e2d9f273d64f98aa36d977b80121094f057..c70b7fa7817a40da51f15cddedb7ddfb6db6aa18 100644 (file)
--- a/ccan/alloc/alloc.c
+++ b/ccan/alloc/alloc.c
@@ -822,6 +822,53 @@ void alloc_free(void *pool, unsigned long poolsize, void *free)
        }
 }
 
+unsigned long alloc_size(void *pool, unsigned long poolsize, void *p)
+{
+       unsigned long len, pagenum;
+       struct metaheader *mh;
+
+       assert(poolsize >= MIN_SIZE);
+
+       mh = first_mheader(pool, poolsize);
+       assert((char *)p >= (char *)(mh + 1));
+       assert((char *)pool + poolsize > (char *)p);
+
+       pagenum = pool_offset(pool, p) / getpagesize();
+
+       if (get_page_state(pool, pagenum) == SPECIAL) {
+               unsigned long off = (unsigned long)p % getpagesize();
+               uint8_t *metadata = get_page_metadata(pool, pagenum);
+               enum sub_metadata_type type = get_bit_pair(metadata, 0);
+
+               assert(off < SUBPAGE_METAOFF);
+
+               switch (type) {
+               case BITMAP:
+                       assert(off % BITMAP_GRANULARITY == 0);
+                       off /= BITMAP_GRANULARITY;
+
+                       /* Offset by one because first bit used for header. */
+                       off++;
+                       len = BITMAP_GRANULARITY;
+                       while (++off < SUBPAGE_METAOFF / BITMAP_GRANULARITY
+                              && get_bit_pair(metadata, off) == TAKEN)
+                               len += BITMAP_GRANULARITY;
+                       break;
+               case UNIFORM:
+                       len = decode_usize(metadata);
+                       break;
+               default:
+                       assert(0);
+               }
+       } else {
+               len = getpagesize();
+               while (get_page_state(pool, ++pagenum) == TAKEN)
+                       len += getpagesize();
+       }
+
+       return len;
+}
+
 static bool is_metadata_page(void *pool, unsigned long poolsize,
                             unsigned long page)
 {

diff --git a/ccan/alloc/alloc.h b/ccan/alloc/alloc.h
index 29c29d078873c0fb335432e9c3bf041be3177d96..d4927141e3e91443deaf956effd488e63765ea8b 100644 (file)
--- a/ccan/alloc/alloc.h
+++ b/ccan/alloc/alloc.h
@@ -7,6 +7,7 @@ void alloc_init(void *pool, unsigned long poolsize);
 void *alloc_get(void *pool, unsigned long poolsize,
                unsigned long size, unsigned long align);
 void alloc_free(void *pool, unsigned long poolsize, void *free);
+unsigned long alloc_size(void *pool, unsigned long poolsize, void *p);
 bool alloc_check(void *pool, unsigned long poolsize);
 
 void alloc_visualize(FILE *out, void *pool, unsigned long poolsize);

diff --git a/ccan/alloc/test/run-testsize.c b/ccan/alloc/test/run-testsize.c
new file mode 100644 (file)
index 0000000..bb063c2
--- /dev/null
+++ b/ccan/alloc/test/run-testsize.c
@@ -0,0 +1,67 @@
+#include "alloc/alloc.h"
+#include "tap/tap.h"
+#include "alloc/alloc.c"
+#include <stdlib.h>
+#include <stdbool.h>
+
+#define POOL_ORD 16
+#define POOL_SIZE (1 << POOL_ORD)
+
+static void invert_bytes(unsigned char *p, unsigned long size)
+{
+       unsigned int i;
+
+       for (i = 0; i < size; i++)
+               p[i] ^= 0xFF;
+}
+
+static bool sizes_ok(void *mem, unsigned long poolsize, void *p[], unsigned num)
+{
+       unsigned int i;
+
+       for (i = 0; i < num; i++)
+               if (alloc_size(mem, poolsize, p[i]) < i)
+                       return false;
+       return true;
+}
+
+int main(int argc, char *argv[])
+{
+       void *mem;
+       unsigned int i, num;
+       void *p[POOL_SIZE];
+
+       plan_tests(5);
+
+       /* FIXME: Needs to be page aligned for now. */
+       posix_memalign(&mem, 1 << POOL_ORD, POOL_SIZE);
+
+       alloc_init(mem, POOL_SIZE);
+
+       /* Check that alloc_size() gives reasonable answers. */
+       for (i = 0; i < POOL_SIZE; i++) {
+               p[i] = alloc_get(mem, POOL_SIZE, i, 1);
+               if (!p[i])
+                       break;
+               invert_bytes(p[i], alloc_size(mem, POOL_SIZE, p[i]));
+       }
+       ok1(i < POOL_SIZE);
+       num = i;
+       ok1(alloc_check(mem, POOL_SIZE));
+       ok1(sizes_ok(mem, POOL_SIZE, p, num));
+
+       /* Free every second one. */
+       for (i = 0; i < num; i+=2) {
+               alloc_free(mem, POOL_SIZE, p[i]);
+               /* Compact. */
+               if (i + 1 < num) {
+                       p[i/2] = p[i + 1];
+                       invert_bytes(p[i/2], alloc_size(mem,POOL_SIZE,p[i/2]));
+               }
+       }
+       num /= 2;
+       ok1(alloc_check(mem, POOL_SIZE));
+       ok1(sizes_ok(mem, POOL_SIZE, p, num));
+
+       return exit_status();
+}

diff --git a/ccan/alloc/test/run.c b/ccan/alloc/test/run.c
index 8cfe8b42ba00d3c40a14a533f6d644426341ff9e..bf8ab479e6b74cb90286fc0a7f4ec5fc3a8907df 100644 (file)
--- a/ccan/alloc/test/run.c
+++ b/ccan/alloc/test/run.c
@@ -49,7 +49,7 @@ int main(int argc, char *argv[])
        unsigned int i, num, max_size;
        void *p[POOL_SIZE];
 
-       plan_tests(139);
+       plan_tests(178);
 
        /* FIXME: Needs to be page aligned for now. */
        posix_memalign(&mem, 1 << POOL_ORD, POOL_SIZE);
@@ -75,6 +75,7 @@ int main(int argc, char *argv[])
        ok1(max_size < POOL_SIZE);
        ok1(max_size > 0);
        ok1(alloc_check(mem, POOL_SIZE));
+       ok1(alloc_size(mem, POOL_SIZE, p[0]) >= max_size);
 
        /* Free it, should be able to reallocate it. */
        alloc_free(mem, POOL_SIZE, p[0]);
@@ -82,6 +83,7 @@ int main(int argc, char *argv[])
 
        p[0] = alloc_get(mem, POOL_SIZE, max_size, 1);
        ok1(p[0]);
+       ok1(alloc_size(mem, POOL_SIZE, p[0]) >= max_size);
        ok1(alloc_check(mem, POOL_SIZE));
        alloc_free(mem, POOL_SIZE, p[0]);
        ok1(alloc_check(mem, POOL_SIZE));
@@ -117,12 +119,14 @@ int main(int argc, char *argv[])
        p[0] = alloc_get(mem, POOL_SIZE, max_size, 1);
        ok1(p[0]);
        ok1(alloc_check(mem, POOL_SIZE));
+       ok1(alloc_size(mem, POOL_SIZE, p[0]) >= max_size);
 
        /* Re-initializing should be the same as freeing everything */
        alloc_init(mem, POOL_SIZE);
        ok1(alloc_check(mem, POOL_SIZE));
        p[0] = alloc_get(mem, POOL_SIZE, max_size, 1);
        ok1(p[0]);
+       ok1(alloc_size(mem, POOL_SIZE, p[0]) >= max_size);
        ok1(alloc_check(mem, POOL_SIZE));
        alloc_free(mem, POOL_SIZE, p[0]);
        ok1(alloc_check(mem, POOL_SIZE));
@@ -133,6 +137,7 @@ int main(int argc, char *argv[])
                ok1(p[i]);
                ok1(((unsigned long)p[i] % (1 << i)) == 0);
                ok1(alloc_check(mem, POOL_SIZE));
+               ok1(alloc_size(mem, POOL_SIZE, p[i]) >= i);
        }
 
        for (i = 0; i < POOL_ORD-1; i++) {
@@ -145,6 +150,7 @@ int main(int argc, char *argv[])
                p[0] = alloc_get(mem, POOL_SIZE, 1, 1 << i);
                ok1(p[0]);
                ok1(alloc_check(mem, POOL_SIZE));
+               ok1(alloc_size(mem, POOL_SIZE, p[i]) >= 1);
                alloc_free(mem, POOL_SIZE, p[0]);
                ok1(alloc_check(mem, POOL_SIZE));
        }
@@ -152,6 +158,7 @@ int main(int argc, char *argv[])
        /* Alignment check for a 0-byte allocation.  Corner case. */
        p[0] = alloc_get(mem, POOL_SIZE, 0, 1 << (POOL_ORD - 1));
        ok1(alloc_check(mem, POOL_SIZE));
+       ok1(alloc_size(mem, POOL_SIZE, p[0]) < POOL_SIZE);
        alloc_free(mem, POOL_SIZE, p[0]);
        ok1(alloc_check(mem, POOL_SIZE));
 
@@ -163,6 +170,7 @@ int main(int argc, char *argv[])
                        break;
        }
        ok1(alloc_check(mem, POOL_SIZE));
+       ok1(alloc_size(mem, POOL_SIZE, p[i-1]) >= getpagesize());
 
        /* Sort them. */
        sort(p, i-1, addr_cmp);
@@ -171,6 +179,7 @@ int main(int argc, char *argv[])
        for (i = 1; p[i]; i++)
                alloc_free(mem, POOL_SIZE, p[i]);
        ok1(alloc_check(mem, POOL_SIZE));
+       ok1(alloc_size(mem, POOL_SIZE, p[0]) >= getpagesize());
 
        /* Now do a whole heap of subpage allocs. */
        for (i = 1; i < POOL_SIZE; i++) {
@@ -185,6 +194,7 @@ int main(int argc, char *argv[])
        ok1(alloc_check(mem, POOL_SIZE));
        p[0] = alloc_get(mem, POOL_SIZE, 1, 1);
        ok1(p[0]);
+       ok1(alloc_size(mem, POOL_SIZE, p[0]) >= 1);
 
        /* Clean up. */
        for (i = 0; p[i]; i++)