Move all the SAA code out of nasmlib

Move all the SAA code out of nasmlib; it's not used by anything than
nasm itself.  Cleaning out the kitchen sink known as nasmlib is a good
thing, too.

1 files changed, 369 insertions, 0 deletions

diff --git a/saa.c b/saa.c
new file mode 100644
index 0000000..340068a
--- /dev/null
+++ b/saa.c
@@ -0,0 +1,369 @@
+#include "compiler.h"
+#include "nasmlib.h"
+#include "saa.h"
+
+/* Aggregate SAA components smaller than this */
+#define SAA_BLKLEN 65536
+
+struct SAA *saa_init(size_t elem_len)
+{
+    struct SAA *s;
+    char *data;
+
+    s = nasm_zalloc(sizeof(struct SAA));
+
+    if (elem_len >= SAA_BLKLEN)
+	s->blk_len = elem_len;
+    else
+	s->blk_len = SAA_BLKLEN - (SAA_BLKLEN % elem_len);
+
+    s->elem_len = elem_len;
+    s->length = s->blk_len;
+    data = nasm_malloc(s->blk_len);
+    s->nblkptrs = s->nblks = 1;
+    s->blk_ptrs = nasm_malloc(sizeof(char *));
+    s->blk_ptrs[0] = data;
+    s->wblk = s->rblk = &s->blk_ptrs[0];
+
+    return s;
+}
+
+void saa_free(struct SAA *s)
+{
+    char **p;
+    size_t n;
+
+    for (p = s->blk_ptrs, n = s->nblks; n; p++, n--)
+	nasm_free(*p);
+
+    nasm_free(s->blk_ptrs);
+    nasm_free(s);
+}
+
+/* Add one allocation block to an SAA */
+static void saa_extend(struct SAA *s)
+{
+    size_t blkn = s->nblks++;
+
+    if (blkn >= s->nblkptrs) {
+	size_t rindex = s->rblk - s->blk_ptrs;
+	size_t windex = s->wblk - s->blk_ptrs;
+
+	s->nblkptrs <<= 1;
+	s->blk_ptrs = nasm_realloc(s->blk_ptrs, s->nblkptrs*sizeof(char *));
+
+	s->rblk = s->blk_ptrs + rindex;
+	s->wblk = s->blk_ptrs + windex;
+    }
+
+    s->blk_ptrs[blkn] = nasm_malloc(s->blk_len);
+    s->length += s->blk_len;
+}
+
+void *saa_wstruct(struct SAA *s)
+{
+    void *p;
+
+    if (s->wpos % s->elem_len)
+	    nasm_malloc_error(ERR_PANIC|ERR_NOFILE,
+			      "misaligned wpos in saa_wstruct");
+
+    if (s->wpos + s->elem_len > s->blk_len) {
+	if (s->wpos != s->blk_len)
+	    nasm_malloc_error(ERR_PANIC|ERR_NOFILE,
+			      "unfilled block in saa_wstruct");
+
+	if (s->wptr + s->elem_len > s->length)
+	    saa_extend(s);
+	s->wblk++;
+	s->wpos = 0;
+    }
+
+    p = *s->wblk + s->wpos;
+    s->wpos += s->elem_len;
+    s->wptr += s->elem_len;
+
+    if (s->wptr > s->datalen)
+	s->datalen = s->wptr;
+
+    return p;
+}
+
+void saa_wbytes(struct SAA *s, const void *data, size_t len)
+{
+    const char *d = data;
+
+    while (len) {
+        size_t l = s->blk_len - s->wpos;
+        if (l > len)
+            l = len;
+        if (l) {
+            if (d) {
+                memcpy(*s->wblk + s->wpos, d, l);
+                d += l;
+            } else
+                memset(*s->wblk + s->wpos, 0, l);
+            s->wpos += l;
+	    s->wptr += l;
+            len -= l;
+
+	    if (s->datalen < s->wptr)
+		s->datalen = s->wptr;
+        }
+        if (len) {
+	    if (s->wptr >= s->length)
+		saa_extend(s);
+	    s->wblk++;
+	    s->wpos = 0;
+	}
+    }
+}
+
+void saa_rewind(struct SAA *s)
+{
+    s->rblk = s->blk_ptrs;
+    s->rpos = s->rptr = 0;
+}
+
+void *saa_rstruct(struct SAA *s)
+{
+    void *p;
+
+    if (s->rptr + s->elem_len > s->datalen)
+	return NULL;
+
+    if (s->rpos % s->elem_len)
+	    nasm_malloc_error(ERR_PANIC|ERR_NOFILE,
+			      "misaligned rpos in saa_rstruct");
+
+    if (s->rpos + s->elem_len > s->blk_len) {
+	s->rblk++;
+	s->rpos = 0;
+    }
+
+    p = *s->rblk + s->rpos;
+    s->rpos += s->elem_len;
+    s->rptr += s->elem_len;
+
+    return p;
+}
+
+const void *saa_rbytes(struct SAA *s, size_t *lenp)
+{
+    const void *p;
+    size_t len;
+
+    if (s->rptr >= s->datalen) {
+	*lenp = 0;
+	return NULL;
+    }
+
+    if (s->rpos >= s->blk_len) {
+	s->rblk++;
+	s->rpos = 0;
+    }
+
+    len = *lenp;
+    if (len > s->datalen - s->rptr)
+	len = s->datalen - s->rptr;
+    if (len > s->blk_len - s->rpos)
+	len = s->blk_len - s->rpos;
+
+    *lenp = len;
+    p = *s->rblk + s->rpos;
+
+    s->rpos += len;
+    s->rptr += len;
+
+    return p;
+}
+
+void saa_rnbytes(struct SAA *s, void *data, size_t len)
+{
+    char *d = data;
+
+    if (s->rptr + len > s->datalen) {
+	nasm_malloc_error(ERR_PANIC|ERR_NOFILE, "overrun in saa_rnbytes");
+	return;
+    }
+
+    while (len) {
+        size_t l;
+	const void *p;
+
+	l = len;
+	p = saa_rbytes(s, &l);
+
+	memcpy(d, p, l);
+	d   += l;
+	len -= l;
+    }
+}
+
+/* Same as saa_rnbytes, except position the counter first */
+void saa_fread(struct SAA *s, size_t posn, void *data, size_t len)
+{
+    size_t ix;
+
+    if (posn+len > s->datalen) {
+	nasm_malloc_error(ERR_PANIC|ERR_NOFILE, "overrun in saa_fread");
+	return;
+    }
+
+    ix = posn / s->blk_len;
+    s->rptr = posn;
+    s->rpos = posn % s->blk_len;
+    s->rblk = &s->blk_ptrs[ix];
+
+    saa_rnbytes(s, data, len);
+}
+
+/* Same as saa_wbytes, except position the counter first */
+void saa_fwrite(struct SAA *s, size_t posn, const void *data, size_t len)
+{
+    size_t ix;
+
+    if (posn > s->datalen) {
+	/* Seek beyond the end of the existing array not supported */
+	nasm_malloc_error(ERR_PANIC|ERR_NOFILE, "overrun in saa_fwrite");
+	return;
+    }
+
+    ix = posn / s->blk_len;
+    s->wptr = posn;
+    s->wpos = posn % s->blk_len;
+    s->wblk = &s->blk_ptrs[ix];
+
+    if (!s->wpos) {
+	s->wpos = s->blk_len;
+	s->wblk--;
+    }
+
+    saa_wbytes(s, data, len);
+}
+
+void saa_fpwrite(struct SAA *s, FILE * fp)
+{
+    const char *data;
+    size_t len;
+
+    saa_rewind(s);
+    while (len = s->datalen, (data = saa_rbytes(s, &len)) != NULL)
+        fwrite(data, 1, len, fp);
+}
+
+void saa_write8(struct SAA *s, uint8_t v)
+{
+    saa_wbytes(s, &v, 1);
+}
+
+#ifdef WORDS_LITTEENDIAN
+
+void saa_write16(struct SAA *s, uint16_t v)
+{
+    saa_wbytes(s, &v, 2);
+}
+
+void saa_write32(struct SAA *s, uint32_t v)
+{
+    saa_wbytes(s, &v, 4);
+}
+
+void saa_write64(struct SAA *s, uint64_t v)
+{
+    saa_wbytes(s, &v, 8);
+}
+
+#else /* not WORDS_LITTLEENDIAN */
+
+void saa_write16(struct SAA *s, uint16_t v)
+{
+    uint8_t b[2];
+
+    b[0] = v;
+    b[1] = v >> 8;
+    saa_wbytes(s, b, 2);
+}
+
+void saa_write32(struct SAA *s, uint32_t v)
+{
+    uint8_t b[4];
+
+    b[0] = v;
+    b[1] = v >> 8;
+    b[2] = v >> 16;
+    b[3] = v >> 24;
+    saa_wbytes(s, b, 4);
+}
+
+void saa_write64(struct SAA *s, uint64_t v)
+{
+    uint8_t b[8];
+
+    b[0] = v;
+    b[1] = v >> 8;
+    b[2] = v >> 16;
+    b[3] = v >> 24;
+    b[4] = v >> 32;
+    b[5] = v >> 40;
+    b[6] = v >> 48;
+    b[7] = v >> 56;
+    saa_wbytes(s, b, 8);
+}
+
+#endif	/* WORDS_LITTLEENDIAN */
+
+/* write unsigned LEB128 value to SAA */
+void saa_wleb128u(struct SAA *psaa, int value)
+{
+  char temp[64], *ptemp;
+  uint8_t byte;
+  int len;
+
+  ptemp = temp;
+  len = 0;
+  do
+  {
+     byte = value & 127;
+     value >>= 7;
+     if (value != 0) /* more bytes to come */
+        byte |= 0x80;
+     *ptemp = byte;
+     ptemp++;
+     len++;
+  } while (value != 0);
+  saa_wbytes(psaa, temp, len);
+}
+
+/* write signed LEB128 value to SAA */
+void saa_wleb128s(struct SAA *psaa, int value)
+{
+  char temp[64], *ptemp;
+  uint8_t byte;
+  bool more, negative;
+  int size, len;
+
+  ptemp = temp;
+  more = 1;
+  negative = (value < 0);
+  size = sizeof(int) * 8;
+  len = 0;
+  while(more)
+  {
+    byte = value & 0x7f;
+    value >>= 7;
+    if (negative)
+     /* sign extend */
+     value |= - (1 <<(size - 7));
+    /* sign bit of byte is second high order bit (0x40) */
+    if ((value == 0 && ! (byte & 0x40)) ||
+       ((value == -1) && (byte & 0x40)))
+       more = 0;
+    else
+      byte |= 0x80;
+    *ptemp = byte;
+    ptemp++;
+    len++;
+  }
+  saa_wbytes(psaa, temp, len);
+}