21 lines
936 B
C
21 lines
936 B
C
//
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// assembler macros to create x86 segments
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//
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#define SEG_NULLASM \
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.word 0, 0; \
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.byte 0, 0, 0, 0
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// The 0xC0 means the limit is in 4096-byte units
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// and (for executable segments) 32-bit mode.
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#define SEG_ASM(type,base,lim) \
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.word (((lim) >> 12) & 0xffff), ((base) & 0xffff); \
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.byte (((base) >> 16) & 0xff), (0x90 | (type)), \
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(0xC0 | (((lim) >> 28) & 0xf)), (((base) >> 24) & 0xff)
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#define STA_X 0x8 // Executable segment
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#define STA_E 0x4 // Expand down (non-executable segments)
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#define STA_C 0x4 // Conforming code segment (executable only)
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#define STA_W 0x2 // Writeable (non-executable segments)
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#define STA_R 0x2 // Readable (executable segments)
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#define STA_A 0x1 // Accessed
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