Zlib ng

2026-05-31 04:56:20 +00:00 · 2019-06-30 18:13:46 -07:00
parent d7c110041a
commit e086f53b97
116 changed files with 30587 additions and 13 deletions
@@ -0,0 +1,86 @@
+/* dfltcc_deflate.c - IBM Z DEFLATE CONVERSION CALL general support. */
+
+#include "zbuild.h"
+#include "dfltcc_common.h"
+#include "dfltcc_detail.h"
+
+/*
+   Memory management.
+
+   DFLTCC requires parameter blocks and window to be aligned. zlib-ng allows
+   users to specify their own allocation functions, so using e.g.
+   `posix_memalign' is not an option. Thus, we overallocate and take the
+   aligned portion of the buffer.
+*/
+static inline int is_dfltcc_enabled(void)
+{
+    uint64_t facilities[(DFLTCC_FACILITY / 64) + 1];
+    register uint8_t r0 __asm__("r0");
+
+    memset(facilities, 0, sizeof(facilities));
+    r0 = sizeof(facilities) / sizeof(facilities[0]) - 1;
+    __asm__ volatile("stfle %[facilities]\n" : [facilities] "=Q" (facilities), [r0] "+r" (r0) :: "cc");
+    return is_bit_set((const char *)facilities, DFLTCC_FACILITY);
+}
+
+void ZLIB_INTERNAL dfltcc_reset(PREFIX3(streamp) strm, uInt size)
+{
+    struct dfltcc_state *dfltcc_state = (struct dfltcc_state *)((char *)strm->state + size);
+    struct dfltcc_qaf_param *param = (struct dfltcc_qaf_param *)&dfltcc_state->param;
+
+    /* Initialize available functions */
+    if (is_dfltcc_enabled()) {
+        dfltcc(DFLTCC_QAF, param, NULL, NULL, NULL, NULL, NULL);
+        memmove(&dfltcc_state->af, param, sizeof(dfltcc_state->af));
+    } else
+        memset(&dfltcc_state->af, 0, sizeof(dfltcc_state->af));
+
+    /* Initialize parameter block */
+    memset(&dfltcc_state->param, 0, sizeof(dfltcc_state->param));
+    dfltcc_state->param.nt = 1;
+
+    /* Initialize tuning parameters */
+    dfltcc_state->level_mask = DFLTCC_LEVEL_MASK;
+    dfltcc_state->block_size = DFLTCC_BLOCK_SIZE;
+    dfltcc_state->block_threshold = DFLTCC_FIRST_FHT_BLOCK_SIZE;
+    dfltcc_state->dht_threshold = DFLTCC_DHT_MIN_SAMPLE_SIZE;
+    dfltcc_state->param.ribm = DFLTCC_RIBM;
+}
+
+void ZLIB_INTERNAL *dfltcc_alloc_state(PREFIX3(streamp) strm, uInt items, uInt size)
+{
+    Assert((items * size) % 8 == 0,
+           "The size of zlib-ng state must be a multiple of 8");
+    return ZALLOC(strm, items * size + sizeof(struct dfltcc_state), sizeof(unsigned char));
+}
+
+void ZLIB_INTERNAL dfltcc_copy_state(void *dst, const void *src, uInt size)
+{
+    memcpy(dst, src, size + sizeof(struct dfltcc_state));
+}
+
+static const int PAGE_ALIGN = 0x1000;
+
+#define ALIGN_UP(p, size) (__typeof__(p))(((uintptr_t)(p) + ((size) - 1)) & ~((size) - 1))
+
+void ZLIB_INTERNAL *dfltcc_alloc_window(PREFIX3(streamp) strm, uInt items, uInt size)
+{
+    void *p;
+    void *w;
+
+    /* To simplify freeing, we store the pointer to the allocated buffer right
+     * before the window.
+     */
+    p = ZALLOC(strm, sizeof(void *) + items * size + PAGE_ALIGN, sizeof(unsigned char));
+    if (p == NULL)
+        return NULL;
+    w = ALIGN_UP((char *)p + sizeof(void *), PAGE_ALIGN);
+    *(void **)((char *)w - sizeof(void *)) = p;
+    return w;
+}
+
+void ZLIB_INTERNAL dfltcc_free_window(PREFIX3(streamp) strm, void *w)
+{
+    if (w)
+        ZFREE(strm, *(void **)((unsigned char *)w - sizeof(void *)));
+}