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segment.hpp File Reference

Functions that deal with segments. More...


class  segment_t
 Describes a program segment. More...
class  lock_segment
 Helper class to lock a segment pointer so it stays valid. More...


#define SREG_NUM   16
 Maximum number of segment registers is 16 (see segregs.hpp)
#define saAbs   0
 Absolute segment.
#define saRelByte   1
 Relocatable, byte aligned.
#define saRelWord   2
 Relocatable, word (2-byte) aligned.
#define saRelPara   3
 Relocatable, paragraph (16-byte) aligned.
#define saRelPage   4
 Relocatable, aligned on 256-byte boundary.
#define saRelDble   5
 Relocatable, aligned on a double word (4-byte) boundary. More...
#define saRel4K   6
 This value is used by the PharLap OMF for page (4K) alignment. More...
#define saGroup   7
 Segment group.
#define saRel32Bytes   8
 32 bytes
#define saRel64Bytes   9
 64 bytes
#define saRelQword   10
 8 bytes
#define saRel128Bytes   11
 128 bytes
#define saRel512Bytes   12
 512 bytes
#define saRel1024Bytes   13
 1024 bytes
#define saRel2048Bytes   14
 2048 bytes
#define saRel_MAX_ALIGN_CODE   saRel2048Bytes
#define scPriv   0
 Private. More...
#define scGroup   1
 Segment group.
#define scPub   2
 Public. More...
#define scPub2   4
 As defined by Microsoft, same as C=2 (public).
#define scStack   5
 Stack. More...
#define scCommon   6
 Common. Combine by overlay using maximum size.
#define scPub3   7
 As defined by Microsoft, same as C=2 (public).
#define sc_MAX_COMB_CODE   scPub3
#define SEGPERM_EXEC   1
#define SEGPERM_WRITE   2
#define SEGPERM_READ   4
#define SFL_COMORG   0x01
 IDP dependent field (IBM PC: if set, ORG directive is not commented out)
#define SFL_OBOK   0x02
 Orgbase is present? (IDP dependent field)
#define SFL_HIDDEN   0x04
 Is the segment hidden?
#define SFL_DEBUG   0x08
 Is the segment created for the debugger?. More...
#define SFL_LOADER   0x10
 Is the segment created by the loader?
#define SFL_HIDETYPE   0x20
 Hide segment type (do not print it in the listing)
#define SFL_HEADER   0x40
 Header segment (do not create offsets to it in the disassembly)
#define SEG_NORM   0
 unknown type, no assumptions
#define SEG_XTRN   1
 * segment with 'extern' definitions. More...
#define SEG_CODE   2
 code segment
#define SEG_DATA   3
 data segment
#define SEG_IMP   4
 java: implementation segment
#define SEG_GRP   6
 * group of segments
#define SEG_NULL   7
 zero-length segment
#define SEG_UNDF   8
 undefined segment type (not used)
#define SEG_BSS   9
 uninitialized segment
#define SEG_ABSSYM   10
 * segment with definitions of absolute symbols
#define SEG_COMM   11
 * segment with communal definitions
#define SEG_IMEM   12
 internal processor memory & sfr (8051)
#define ADDSEG_NOSREG   0x0001
 set all default segment register values to BADSEL (undefine all default segment registers)
#define ADDSEG_OR_DIE   0x0002
 qexit() if can't add a segment
#define ADDSEG_NOTRUNC   0x0004
 don't truncate the new segment at the beginning of the next segment if they overlap. More...
#define ADDSEG_QUIET   0x0008
 silent mode, no "Adding segment..." in the messages window
#define ADDSEG_FILLGAP   0x0010
 fill gap between new segment and previous one. More...
#define ADDSEG_SPARSE   0x0020
 use sparse storage method for the new ranges of the created segment. More...
#define ADDSEG_NOAA   0x0040
 do not mark new segment for auto-analysis
#define ADDSEG_IDBENC   0x0080
 'name' and 'sclass' are given in the IDB encoding; non-ASCII bytes will be decoded accordingly
#define SEGMOD_KILL   0x0001
 disable addresses if segment gets shrinked or deleted
#define SEGMOD_KEEP   0x0002
 keep information (code & data, etc)
#define SEGMOD_SILENT   0x0004
 be silent
#define SEGMOD_KEEP0   0x0008
 flag for internal use, don't set
#define SEGMOD_KEEPSEL   0x0010
 do not try to delete unused selector
#define SEGMOD_NOMOVE   0x0020
 don't move info from the start of segment to the new start address (for set_segm_start())
#define SEGMOD_SPARSE   0x0040
 use sparse storage if extending the segment (for set_segm_start(), set_segm_end())
#define MSF_SILENT   0x0001
 don't display a "please wait" box on the screen
#define MSF_NOFIX   0x0002
 don't call the loader to fix relocations
#define MSF_LDKEEP   0x0004
 keep the loader in the memory (optimization)
#define MSF_FIXONCE   0x0008
 call loader only once with the special calling method. More...
#define MSF_PRIORITY   0x0020
 loader segments will overwrite any existing debugger segments when moved. More...
#define MSF_NETNODES   0x0080
 move netnodes instead of changing inf.netdelta (this is slower); valid for rebase_program()
#define CSS_OK   0
#define CSS_NODBG   -1
 debugger is not running
#define CSS_NORANGE   -2
 could not find corresponding memory range
#define CSS_NOMEM   -3
 not enough memory (might be because the segment is too big)
#define CSS_BREAK   -4
 memory reading process stopped by user
#define SNAP_ALL_SEG   0
 Take a snapshot of all segments.
#define SNAP_LOAD_SEG   1
 Take a snapshot of loader segments.
#define SNAP_CUR_SEG   2
 Take a snapshot of current segment.
#define MAX_GROUPS   8
 max number of segment groups
 max number of segment translations


enum  move_segm_code_t {


 CASSERT (sizeof(segment_t)==104)
bool is_visible_segm (segment_t *s)
bool is_finally_visible_segm (segment_t *s)
idaman void ida_export set_visible_segm (segment_t *s, bool visible)
idaman bool ida_export is_spec_segm (uchar seg_type)
 Has segment a special type?. More...
idaman bool ida_export is_spec_ea (ea_t ea)
 Does the address belong to a segment with a special type?. More...
idaman void ida_export lock_segm (const segment_t *segm, bool lock)
 Lock segment pointer Locked pointers are guaranteed to remain valid until they are unlocked. More...
idaman bool ida_export is_segm_locked (const segment_t *segm)
 Is a segment pointer locked?
idaman bool ida_export getn_selector (sel_t *sel, ea_t *base, int n)
 Get description of selector (0..get_selector_qty()-1)
idaman size_t ida_export get_selector_qty (void)
 Get number of defined selectors.
idaman sel_t ida_export setup_selector (ea_t segbase)
 Allocate a selector for a segment if necessary. More...
idaman sel_t ida_export allocate_selector (ea_t segbase)
 Allocate a selector for a segment unconditionally. More...
idaman sel_t ida_export find_free_selector (void)
 Find first unused selector. More...
idaman int ida_export set_selector (sel_t selector, ea_t paragraph)
 Set mapping of selector to a paragraph. More...
idaman void ida_export del_selector (sel_t selector)
 Delete mapping of a selector. More...
idaman ea_t ida_export sel2para (sel_t selector)
 Get mapping of a selector. More...
ea_t idaapi sel2ea (sel_t selector)
 Get mapping of a selector as a linear address. More...
idaman sel_t ida_export find_selector (ea_t base)
 Find a selector that has mapping to the specified paragraph. More...
idaman int ida_export enumerate_selectors (int(idaapi *func)(sel_t sel, ea_t para))
 Enumerate all selectors from the translation table. More...
idaman ea_t ida_export enumerate_segments_with_selector (sel_t selector, ea_t(idaapi *func)(segment_t *s, void *ud), void *ud=nullptr)
 Enumerate all segments with the specified selector. More...
idaman segment_t *ida_export get_segm_by_sel (sel_t selector)
 Get pointer to segment structure. More...
idaman bool ida_export add_segm_ex (segment_t *NONNULL s, const char *name, const char *sclass, int flags)
 Add a new segment. More...
idaman bool ida_export add_segm (ea_t para, ea_t start, ea_t end, const char *name, const char *sclass, int flags=0)
 Add a new segment, second form. More...
idaman bool ida_export del_segm (ea_t ea, int flags)
 Delete a segment. More...
idaman int ida_export get_segm_qty (void)
 Get number of segments.
idaman segment_t *ida_export getseg (ea_t ea)
 Get pointer to segment by linear address. More...
idaman segment_t *ida_export getnseg (int n)
 Get pointer to segment by its number. More...
idaman int ida_export get_segm_num (ea_t ea)
 Get number of segment by address. More...
idaman segment_t *ida_export get_next_seg (ea_t ea)
 Get pointer to the next segment.
idaman segment_t *ida_export get_prev_seg (ea_t ea)
 Get pointer to the previous segment.
idaman segment_t *ida_export get_first_seg (void)
 Get pointer to the first segment.
idaman segment_t *ida_export get_last_seg (void)
 Get pointer to the last segment.
idaman segment_t *ida_export get_segm_by_name (const char *name)
 Get pointer to segment by its name. More...
idaman bool ida_export set_segm_end (ea_t ea, ea_t newend, int flags)
 Set segment end address. More...
idaman bool ida_export set_segm_start (ea_t ea, ea_t newstart, int flags)
 Set segment start address. More...
idaman bool ida_export move_segm_start (ea_t ea, ea_t newstart, int mode)
 Move segment start. More...
idaman const char *ida_export move_segm_strerror (move_segm_code_t code)
 Return string describing error MOVE_SEGM_... code.
idaman move_segm_code_t ida_export move_segm (segment_t *s, ea_t to, int flags=0)
 This function moves all information to the new address. More...
idaman move_segm_code_t ida_export rebase_program (adiff_t delta, int flags)
 Rebase the whole program by 'delta' bytes. More...
idaman int ida_export change_segment_status (segment_t *s, bool is_deb_segm)
 Convert a debugger segment to a regular segment and vice versa. More...
idaman bool ida_export take_memory_snapshot (int type)
 Take a memory snapshot of the running process. More...
idaman bool ida_export is_miniidb (void)
 Is the database a miniidb created by the debugger?. More...
idaman bool ida_export set_segm_base (segment_t *s, ea_t newbase)
 Internal function.
idaman int ida_export set_group_selector (sel_t grp, sel_t sel)
 Create a new group of segments (used OMF files). More...
idaman sel_t ida_export get_group_selector (sel_t grpsel)
 Get common selector for a group of segments. More...
idaman bool ida_export add_segment_translation (ea_t segstart, ea_t mappedseg)
 Add segment translation. More...
idaman bool ida_export set_segment_translations (ea_t segstart, const eavec_t &transmap)
 Set new translation list. More...
idaman void ida_export del_segment_translations (ea_t segstart)
 Delete the translation list. More...
idaman ssize_t ida_export get_segment_translations (eavec_t *transmap, ea_t segstart)
 Get segment translation list. More...
idaman ssize_t ida_export get_segment_cmt (qstring *buf, const segment_t *s, bool repeatable)
 Get segment comment. More...
idaman void ida_export set_segment_cmt (const segment_t *s, const char *cmt, bool repeatable)
 Set segment comment. More...
idaman void ida_export std_out_segm_footer (struct outctx_t &ctx, segment_t *seg)
 Generate segment footer line as a comment line. More...
idaman int ida_export set_segm_name (segment_t *s, const char *name, int flags=0)
 Rename segment. More...
idaman ssize_t ida_export get_segm_name (qstring *buf, const segment_t *s, int flags=0)
 Get true segment name by pointer to segment. More...
ssize_t idaapi get_visible_segm_name (qstring *buf, const segment_t *s)
 Get segment name by pointer to segment. More...
ssize_t get_segm_expr (qstring *buf, ea_t from, sel_t sel)
 Get colored segment name expression in the form (segname + displacement). More...
idaman ssize_t ida_export get_segm_class (qstring *buf, const segment_t *s)
 Get segment class. More...
idaman int ida_export set_segm_class (segment_t *s, const char *sclass, int flags=0)
 Set segment class. More...
idaman uchar ida_export segtype (ea_t ea)
 Get segment type. More...
idaman const char *ida_export get_segment_alignment (uchar align)
 Get text representation of segment alignment code. More...
idaman const char *ida_export get_segment_combination (uchar comb)
 Get text representation of segment combination code. More...
idaman ea_t ida_export get_segm_para (const segment_t *s)
 Get segment base paragraph. More...
idaman ea_t ida_export get_segm_base (const segment_t *s)
 Get segment base linear address. More...
idaman bool ida_export set_segm_addressing (segment_t *s, size_t bitness)
 Change segment addressing mode (16, 32, 64 bits). More...
bool is_debugger_segm (ea_t ea)
 Does the address belong to a debug segment?
bool is_ephemeral_segm (ea_t ea)
 Does the address belong to an ephemeral segment?
idaman ea_t ida_export correct_address (ea_t ea, ea_t from, ea_t to, ea_t size, bool skip_check=false)
idaman bool ida_export update_segm (segment_t *s)
idaman adiff_t ida_export segm_adjust_diff (const segment_t *s, adiff_t delta)
 Truncate and sign extend a delta depending on the segment.
idaman ea_t ida_export segm_adjust_ea (const segment_t *s, ea_t ea)
 Truncate an address depending on the segment.

Detailed Description

Functions that deal with segments.

IDA requires that all program addresses belong to segments (each address must belong to exactly one segment). The situation when an address doesn't belong to any segment is allowed as a temporary situation only when the user changes program segmentation. Bytes outside a segment can't be converted to instructions, have names, comments, etc. Each segment has its start address, ending address and represents a contiguous range of addresses. There might be unused holes between segments.

Each segment has its unique segment selector. This selector is used to distinguish the segment from other segments. For 16-bit programs the selector is equal to the segment base paragraph. For 32-bit programs there is special array to translate the selectors to the segment base paragraphs. A selector is a 32/64 bit value.

The segment base paragraph determines the offsets in the segment. If the start address of the segment == (base << 4) then the first offset in the segment will be 0. The start address should be higher or equal to (base << 4). We will call the offsets in the segment 'virtual addresses'. So, the virtual address of the first byte of the segment is

(start address of segment - segment base linear address)

For IBM PC, the virtual address corresponds to the offset part of the address. For other processors (Z80, for example), virtual addresses correspond to Z80 addresses and linear addresses are used only internally. For MS Windows programs the segment base paragraph is 0 and therefore the segment virtual addresses are equal to linear addresses.