Initial revision

src/arch/i386/core/aout_loader.c

@@ -0,0 +1,144 @@
+/* a.out */
+struct exec {
+	unsigned long      a_midmag;	/* flags<<26 | mid<<16 | magic */
+	unsigned long      a_text;	/* text segment size */
+	unsigned long      a_data;	/* initialized data size */
+	unsigned long      a_bss;	/* uninitialized data size */
+	unsigned long      a_syms;	/* symbol table size */
+	unsigned long      a_entry;	/* entry point */
+	unsigned long      a_trsize;	/* text relocation size */
+	unsigned long      a_drsize;	/* data relocation size */
+};
+
+struct aout_state {
+	struct exec head;
+	unsigned long curaddr;
+	int segment;			/* current segment number, -1 for none */
+	unsigned long loc;		/* start offset of current block */
+	unsigned long skip;		/* padding to be skipped to current segment */
+	unsigned long toread;		/* remaining data to be read in the segment */
+};
+
+static struct aout_state astate;
+
+static sector_t aout_download(unsigned char *data, unsigned int len, int eof);
+static inline os_download_t aout_probe(unsigned char *data, unsigned int len)
+{
+	unsigned long start, mid, end, istart, iend;
+	if (len < sizeof(astate.head)) {
+		return 0;
+	}
+	memcpy(&astate.head, data, sizeof(astate.head));
+	if ((astate.head.a_midmag & 0xffff) != 0x010BL) {
+		return 0;
+	}
+	
+	printf("(a.out");
+	aout_freebsd_probe();
+	printf(")... ");
+	/* Check the aout image */
+	start  = astate.head.a_entry;
+	mid    = (((start + astate.head.a_text) + 4095) & ~4095) + astate.head.a_data;
+	end    = ((mid + 4095) & ~4095) + astate.head.a_bss;
+	istart = 4096;
+	iend   = istart + (mid - start);
+	if (!prep_segment(start, mid, end, istart, iend))
+		return dead_download;
+	astate.segment = -1;
+	astate.loc = 0;
+	astate.skip = 0;
+	astate.toread = 0;
+	return aout_download;
+}
+
+static sector_t aout_download(unsigned char *data, unsigned int len, int eof)
+{
+	unsigned int offset;	/* working offset in the current data block */
+
+	offset = 0;
+
+#ifdef AOUT_LYNX_KDI
+	astate.segment++;
+	if (astate.segment == 0) {
+		astate.curaddr = 0x100000;
+		astate.head.a_entry = astate.curaddr + 0x20;
+	}
+	memcpy(phys_to_virt(astate.curaddr), data, len);
+	astate.curaddr += len;
+	return 0;
+#endif
+
+	do {
+		if (astate.segment != -1) {
+			if (astate.skip) {
+				if (astate.skip >= len - offset) {
+					astate.skip -= len - offset;
+					break;
+				}
+				offset += astate.skip;
+				astate.skip = 0;
+			}
+
+			if (astate.toread) {
+				if (astate.toread >= len - offset) {
+					memcpy(phys_to_virt(astate.curaddr), data+offset,
+						len - offset);
+					astate.curaddr += len - offset;
+					astate.toread -= len - offset;
+					break;
+				}
+				memcpy(phys_to_virt(astate.curaddr), data+offset, astate.toread);
+				offset += astate.toread;
+				astate.toread = 0;
+			}
+		}
+
+		/* Data left, but current segment finished - look for the next
+		 * segment.  This is quite simple for a.out files.  */
+		astate.segment++;
+		switch (astate.segment) {
+		case 0:
+			/* read text */
+			astate.curaddr = astate.head.a_entry;
+			astate.skip = 4096;
+			astate.toread = astate.head.a_text;
+			break;
+		case 1:
+			/* read data */
+			/* skip and curaddr may be wrong, but I couldn't find
+			 * examples where this failed.  There is no reasonable
+			 * documentation for a.out available.  */
+			astate.skip = ((astate.curaddr + 4095) & ~4095) - astate.curaddr;
+			astate.curaddr = (astate.curaddr + 4095) & ~4095;
+			astate.toread = astate.head.a_data;
+			break;
+		case 2:
+			/* initialize bss and start kernel */
+			astate.curaddr = (astate.curaddr + 4095) & ~4095;
+			astate.skip = 0;
+			astate.toread = 0;
+			memset(phys_to_virt(astate.curaddr), '\0', astate.head.a_bss);
+			goto aout_startkernel;
+		default:
+			break;
+		}
+	} while (offset < len);
+
+	astate.loc += len;
+
+	if (eof) {
+		unsigned long entry;
+
+aout_startkernel:
+		entry = astate.head.a_entry;
+		done(1);
+
+		aout_freebsd_boot();
+#ifdef AOUT_LYNX_KDI
+		xstart32(entry);
+#endif
+		printf("unexpected a.out variant\n");
+		longjmp(restart_etherboot, -2);
+	}
+	return 0;
+}