d0f7acf9eb
An x86-64 operating system built from xv6, now largely rewritten: SMP, a copy-on-write root filesystem (SchFS), PCI/USB/virtio drivers, a TTF rasteriser, and a Linux-numbered syscall ABI. No history before this point -- the tree was never under version control. This commit exists so the rename that follows has something to undo to.
24 lines
714 B
Perl
24 lines
714 B
Perl
#!/usr/bin/perl
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# Zero-pads the stage2 bootloader binary out to a fixed size (STAGE2_SECTORS
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# * 512 bytes), so the kernel's on-disk starting sector is predictable
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# regardless of stage2's actual compiled size. Errors out if stage2 has
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# grown past that budget instead of silently truncating it.
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my $size = $ARGV[1] || die "usage: padstage2.pl <file> <size-in-bytes>\n";
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open(F, $ARGV[0]) || die "open $ARGV[0]: $!";
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my $n = sysread(F, my $buf, $size + 1);
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close(F);
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if ($n > $size) {
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print STDERR "stage2 too large: $n bytes (max $size)\n";
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exit 1;
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}
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print STDERR "stage2 is $n bytes (max $size)\n";
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$buf .= "\0" x ($size - $n);
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open(F, ">$ARGV[0]") || die "open >$ARGV[0]: $!";
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print F $buf;
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close(F);
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