fishhook.h

// Copyright (c) 2013, Facebook, Inc.
// All rights reserved.
//
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//
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#ifndef fishhook_h
#define fishhook_h

#include <stddef.h>
#include <stdint.h>

#ifdef __cplusplus
extern "C" {
#endif

/*
 * A structure representing a particular intended rebinding from a symbol
 * name to its replacement.
 */
struct rebinding {
    const char *name;
    void *replacement;
    void **replaced;
};

/*
 * For each rebinding in rebindings, rebinds references to external, indirect
 * symbols with the specified name to instead point at replacement for each
 * image in the calling process as well as for all future images that are loaded
 * by the runtime. If rebind_symbols is called more than once, the symbols to
 * rebind are added to the existing list of rebindings, and if a given symbol
 * is rebound more than once, the later rebinding will take precedence.
 */
int rebind_symbols(struct rebinding rebindings[], size_t rebindings_nel);

/*
 * Rebinds as above, but only in the specified image. The header should point
 * to the mach-o header, the slide should be the slide offset.
 */
int rebind_symbols_image(void *header, intptr_t slide,
                         struct rebinding rebindings[], size_t rebindings_nel);

#ifdef __cplusplus
}
#endif

#endif /* fishhook_h */