NASM 0.91

1 files changed, 303 insertions, 0 deletions

diff --git a/outbin.c b/outbin.c
new file mode 100644
index 0000000..82c8510
--- /dev/null
+++ b/outbin.c
@@ -0,0 +1,303 @@
+/* outbin.c	output routines for the Netwide Assembler to produce
+ *		flat-form binary files
+ *
+ * The Netwide Assembler is copyright (C) 1996 Simon Tatham and
+ * Julian Hall. All rights reserved. The software is
+ * redistributable under the licence given in the file "Licence"
+ * distributed in the NASM archive.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "nasm.h"
+#include "nasmlib.h"
+#include "outform.h"
+
+#ifdef OF_BIN
+
+static FILE *fp;
+static efunc error;
+
+static struct Section {
+    struct SAA *contents;
+    long length;
+    long index;
+} textsect, datasect;
+static long bsslen, bssindex;
+
+static struct Reloc {
+    struct Reloc *next;
+    long posn;
+    long bytes;
+    long secref;
+    long secrel;
+    struct Section *target;
+} *relocs, **reloctail;
+
+static int start_point;
+
+static void add_reloc (struct Section *s, long bytes, long secref,
+		       long secrel) {
+    struct Reloc *r;
+
+    r = *reloctail = nasm_malloc(sizeof(struct Reloc));
+    reloctail = &r->next;
+    r->next = NULL;
+    r->posn = s->length;
+    r->bytes = bytes;
+    r->secref = secref;
+    r->secrel = secrel;
+    r->target = s;
+}
+
+static void bin_init (FILE *afp, efunc errfunc, ldfunc ldef) {
+    fp = afp;
+
+    error = errfunc;
+    (void) ldef;		       /* placate optimisers */
+
+    start_point = 0;		       /* default */
+    textsect.contents = saa_init(1L);
+    datasect.contents = saa_init(1L);
+    textsect.length = datasect.length = 0;
+    textsect.index = seg_alloc();
+    datasect.index = seg_alloc();
+    bsslen = 0;
+    bssindex = seg_alloc();
+    relocs = NULL;
+    reloctail = &relocs;
+}
+
+static void bin_cleanup (void) {
+    struct Reloc *r;
+    long datapos, dataalign, bsspos;
+
+    datapos = (start_point + textsect.length + 3) & ~3;/* align on 4 bytes */
+    dataalign = datapos - (start_point + textsect.length);
+
+    saa_rewind (textsect.contents);
+    saa_rewind (datasect.contents);
+
+    bsspos = (datapos + datasect.length + 3) & ~3;
+
+    for (r = relocs; r; r = r->next) {
+	unsigned char *p, *q, mydata[4];
+	long l;
+
+	saa_fread (r->target->contents, r->posn, mydata, r->bytes);
+	p = q = mydata;
+	l = *p++;
+	l += ((long)*p++) << 8;
+	if (r->bytes == 4) {
+	    l += ((long)*p++) << 16;
+	    l += ((long)*p++) << 24;
+	}
+
+	if (r->secref == textsect.index)
+	    l += start_point;
+	else if (r->secref == datasect.index)
+	    l += datapos;
+	else if (r->secref == bssindex)
+	    l += bsspos;
+
+	if (r->secrel == textsect.index)
+	    l -= start_point;
+	else if (r->secrel == datasect.index)
+	    l -= datapos;
+	else if (r->secrel == bssindex)
+	    l -= bsspos;
+
+	if (r->bytes == 4)
+	    WRITELONG(q, l);
+	else
+	    WRITESHORT(q, l);
+	saa_fwrite (r->target->contents, r->posn, mydata, r->bytes);
+    }
+    saa_fpwrite (textsect.contents, fp);
+    if (datasect.length > 0) {
+	fwrite ("\0\0\0\0", dataalign, 1, fp);
+	saa_fpwrite (datasect.contents, fp);
+    }
+    fclose (fp);
+    saa_free (textsect.contents);
+    saa_free (datasect.contents);
+    while (relocs) {
+	r = relocs->next;
+	nasm_free (relocs);
+	relocs = r;
+    }
+}
+
+static void bin_out (long segto, void *data, unsigned long type,
+		     long segment, long wrt) {
+    unsigned char *p, mydata[4];
+    struct Section *s;
+    long realbytes;
+
+    if (wrt != NO_SEG) {
+	wrt = NO_SEG;		       /* continue to do _something_ */
+	error (ERR_NONFATAL, "WRT not supported by binary output format");
+    }
+
+    /*
+     * handle absolute-assembly (structure definitions)
+     */
+    if (segto == NO_SEG) {
+	if ((type & OUT_TYPMASK) != OUT_RESERVE)
+	    error (ERR_NONFATAL, "attempt to assemble code in [ABSOLUTE]"
+		   " space");
+	return;
+    }
+
+    if (segto == bssindex) {	       /* BSS */
+	if ((type & OUT_TYPMASK) != OUT_RESERVE)
+	    error(ERR_WARNING, "attempt to initialise memory in the"
+		  " BSS section: ignored");
+	s = NULL;
+    } else if (segto == textsect.index) {
+	s = &textsect;
+    } else if (segto == datasect.index) {
+	s = &datasect;
+    } else {
+	error(ERR_WARNING, "attempt to assemble code in"
+	      " segment %d: defaulting to `.text'", segto);
+	s = &textsect;
+    }
+
+    if ((type & OUT_TYPMASK) == OUT_ADDRESS) {
+	if (segment != NO_SEG &&
+	    segment != textsect.index &&
+	    segment != datasect.index &&
+	    segment != bssindex) {
+	    if (segment % 2)
+		error(ERR_NONFATAL, "binary output format does not support"
+		      " segment base references");
+	    else
+		error(ERR_NONFATAL, "binary output format does not support"
+		      " external references");
+	    segment = NO_SEG;
+	}
+	if (s) {
+	    if (segment != NO_SEG)
+		add_reloc (s, type & OUT_SIZMASK, segment, -1L);
+	    p = mydata;
+	    if ((type & OUT_SIZMASK) == 4)
+		WRITELONG (p, *(long *)data);
+	    else
+		WRITESHORT (p, *(long *)data);
+	    saa_wbytes (s->contents, mydata, type & OUT_SIZMASK);
+	    s->length += type & OUT_SIZMASK;
+	} else
+	    bsslen += type & OUT_SIZMASK;
+    } else if ((type & OUT_TYPMASK) == OUT_RAWDATA) {
+	type &= OUT_SIZMASK;
+	p = data;
+	if (s) {
+	    saa_wbytes (s->contents, data, type);
+	    s->length += type;
+	} else
+	    bsslen += type;
+    } else if ((type & OUT_TYPMASK) == OUT_RESERVE) {
+	if (s) {
+	    error(ERR_WARNING, "uninitialised space declared in"
+		  " %s section: zeroing",
+		  (segto == textsect.index ? "code" : "data"));
+	}
+	type &= OUT_SIZMASK;
+	if (s) {
+	    saa_wbytes (s->contents, NULL, type);
+	    s->length += type;
+	} else
+	    bsslen += type;
+    } else if ((type & OUT_TYPMASK) == OUT_REL2ADR ||
+	       (type & OUT_TYPMASK) == OUT_REL4ADR) {
+	realbytes = ((type & OUT_TYPMASK) == OUT_REL4ADR ? 4 : 2);
+	if (segment != NO_SEG &&
+	    segment != textsect.index &&
+	    segment != datasect.index &&
+	    segment != bssindex) {
+	    if (segment % 2)
+		error(ERR_NONFATAL, "binary output format does not support"
+		      " segment base references");
+	    else
+		error(ERR_NONFATAL, "binary output format does not support"
+		      " external references");
+	    segment = NO_SEG;
+	}
+	if (s) {
+	    add_reloc (s, realbytes, segment, segto);
+	    p = mydata;
+	    if (realbytes == 4)
+		WRITELONG (p, *(long*)data - realbytes - s->length);
+	    else
+		WRITESHORT (p, *(long*)data - realbytes - s->length);
+	    saa_wbytes (s->contents, mydata, realbytes);
+	    s->length += realbytes;
+	} else
+	    bsslen += realbytes;
+    }
+}
+
+static void bin_deflabel (char *name, long segment, long offset,
+			  int is_global) {
+    if (is_global == 2) {
+	error (ERR_NONFATAL, "binary output format does not support common"
+	       " variables");
+    }
+}
+
+static long bin_secname (char *name, int pass, int *bits) {
+    /*
+     * Default is 16 bits.
+     */
+    if (!name)
+	*bits = 16;
+
+    if (!name)
+	return textsect.index;
+
+    if (!strcmp(name, ".text"))
+	return textsect.index;
+    else if (!strcmp(name, ".data"))
+	return datasect.index;
+    else if (!strcmp(name, ".bss"))
+	return bssindex;
+    else
+	return NO_SEG;
+}
+
+static long bin_segbase (long segment) {
+    return segment;
+}
+
+static int bin_directive (char *directive, char *value, int pass) {
+    int rn_error;
+
+    if (!strcmp(directive, "org")) {
+	start_point = readnum (value, &rn_error);
+	if (rn_error)
+	    error (ERR_NONFATAL, "argument to ORG should be numeric");
+	return 1;
+    } else
+	return 0;
+}
+
+static void bin_filename (char *inname, char *outname, efunc error) {
+    standard_extension (inname, outname, "", error);
+}
+
+struct ofmt of_bin = {
+    "flat-form binary files (e.g. DOS .COM, .SYS)",
+    "bin",
+    bin_init,
+    bin_out,
+    bin_deflabel,
+    bin_secname,
+    bin_segbase,
+    bin_directive,
+    bin_filename,
+    bin_cleanup
+};
+
+#endif /* OF_BIN */