probe-finder.h

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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _PROBE_FINDER_H
#define _PROBE_FINDER_H

#include <stdbool.h>
#include "intlist.h"
#include "probe-event.h"
#include "sane_ctype.h"

#define MAX_PROBE_BUFFER    1024
#define MAX_PROBES       128
#define MAX_PROBE_ARGS       128

#define PROBE_ARG_VARS      "$vars"
#define PROBE_ARG_PARAMS    "$params"

static inline int is_c_varname(const char *name)
{
    /* TODO */
    return isalpha(name[0]) || name[0] == '_';
}

#ifdef HAVE_DWARF_SUPPORT

#include "dwarf-aux.h"

/* TODO: export debuginfo data structure even if no dwarf support */

/* debug information structure */
struct debuginfo {
    Dwarf       *dbg;
    Dwfl_Module *mod;
    Dwfl        *dwfl;
    Dwarf_Addr  bias;
};

/* This also tries to open distro debuginfo */
struct debuginfo *debuginfo__new(const char *path);
void debuginfo__delete(struct debuginfo *dbg);

/* Find probe_trace_events specified by perf_probe_event from debuginfo */
int debuginfo__find_trace_events(struct debuginfo *dbg,
                 struct perf_probe_event *pev,
                 struct probe_trace_event **tevs);

/* Find a perf_probe_point from debuginfo */
int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
                struct perf_probe_point *ppt);

int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs,
                   bool adjust_offset);

/* Find a line range */
int debuginfo__find_line_range(struct debuginfo *dbg, struct line_range *lr);

/* Find available variables */
int debuginfo__find_available_vars_at(struct debuginfo *dbg,
                      struct perf_probe_event *pev,
                      struct variable_list **vls);

/* Find a src file from a DWARF tag path */
int get_real_path(const char *raw_path, const char *comp_dir,
             char **new_path);

struct probe_finder {
    struct perf_probe_event *pev;       /* Target probe event */

    /* Callback when a probe point is found */
    int (*callback)(Dwarf_Die *sc_die, struct probe_finder *pf);

    /* For function searching */
    int         lno;        /* Line number */
    Dwarf_Addr      addr;       /* Address */
    const char      *fname;     /* Real file name */
    Dwarf_Die       cu_die;     /* Current CU */
    Dwarf_Die       sp_die;
    struct intlist      *lcache;    /* Line cache for lazy match */

    /* For variable searching */
#if _ELFUTILS_PREREQ(0, 142)
    /* Call Frame Information from .eh_frame */
    Dwarf_CFI       *cfi_eh;
    /* Call Frame Information from .debug_frame */
    Dwarf_CFI       *cfi_dbg;
#endif
    Dwarf_Op        *fb_ops;    /* Frame base attribute */
    unsigned int        machine;    /* Target machine arch */
    struct perf_probe_arg   *pvar;      /* Current target variable */
    struct probe_trace_arg  *tvar;      /* Current result variable */
};

struct trace_event_finder {
    struct probe_finder pf;
    Dwfl_Module     *mod;       /* For solving symbols */
    struct probe_trace_event *tevs;     /* Found trace events */
    int         ntevs;      /* Number of trace events */
    int         max_tevs;   /* Max number of trace events */
};

struct available_var_finder {
    struct probe_finder pf;
    Dwfl_Module     *mod;       /* For solving symbols */
    struct variable_list    *vls;       /* Found variable lists */
    int         nvls;       /* Number of variable lists */
    int         max_vls;    /* Max no. of variable lists */
    bool            child;      /* Search child scopes */
};

struct line_finder {
    struct line_range   *lr;        /* Target line range */

    const char      *fname;     /* File name */
    int         lno_s;      /* Start line number */
    int         lno_e;      /* End line number */
    Dwarf_Die       cu_die;     /* Current CU */
    Dwarf_Die       sp_die;
    int         found;
};

#endif /* HAVE_DWARF_SUPPORT */

#endif /*_PROBE_FINDER_H */