qemu

1
/*
2
 * Utility function to get QEMU's own process map
3
 *
4
 * Copyright (c) 2020 Linaro Ltd
5
 *
6
 * SPDX-License-Identifier: GPL-2.0-or-later
7
 */
8

9
#include "qemu/osdep.h"
10
#include "qemu/cutils.h"
11
#include "qemu/selfmap.h"
12

13
IntervalTreeRoot *read_self_maps(void)
14
{
15
    IntervalTreeRoot *root;
16
    gchar *maps, **lines;
17
    guint i, nlines;
18

19
    if (!g_file_get_contents("/proc/self/maps", &maps, NULL, NULL)) {
20
        return NULL;
21
    }
22

23
    root = g_new0(IntervalTreeRoot, 1);
24
    lines = g_strsplit(maps, "\n", 0);
25
    nlines = g_strv_length(lines);
26

27
    for (i = 0; i < nlines; i++) {
28
        gchar **fields = g_strsplit(lines[i], " ", 6);
29
        guint nfields = g_strv_length(fields);
30

31
        if (nfields > 4) {
32
            uint64_t start, end, offset, inode;
33
            unsigned dev_maj, dev_min;
34
            int errors = 0;
35
            const char *p;
36

37
            errors |= qemu_strtou64(fields[0], &p, 16, &start);
38
            errors |= qemu_strtou64(p + 1, NULL, 16, &end);
39
            errors |= qemu_strtou64(fields[2], NULL, 16, &offset);
40
            errors |= qemu_strtoui(fields[3], &p, 16, &dev_maj);
41
            errors |= qemu_strtoui(p + 1, NULL, 16, &dev_min);
42
            errors |= qemu_strtou64(fields[4], NULL, 10, &inode);
43

44
            if (!errors) {
45
                size_t path_len;
46
                MapInfo *e;
47

48
                if (nfields == 6) {
49
                    p = fields[5];
50
                    p += strspn(p, " ");
51
                    path_len = strlen(p) + 1;
52
                } else {
53
                    p = NULL;
54
                    path_len = 0;
55
                }
56

57
                e = g_malloc0(sizeof(*e) + path_len);
58

59
                e->itree.start = start;
60
                e->itree.last = end - 1;
61
                e->offset = offset;
62
                e->dev = makedev(dev_maj, dev_min);
63
                e->inode = inode;
64

65
                e->is_read  = fields[1][0] == 'r';
66
                e->is_write = fields[1][1] == 'w';
67
                e->is_exec  = fields[1][2] == 'x';
68
                e->is_priv  = fields[1][3] == 'p';
69

70
                if (path_len) {
71
                    e->path = memcpy(e + 1, p, path_len);
72
                }
73

74
                interval_tree_insert(&e->itree, root);
75
            }
76
        }
77
        g_strfreev(fields);
78
    }
79
    g_strfreev(lines);
80
    g_free(maps);
81

82
    return root;
83
}
84

85
/**
86
 * free_self_maps:
87
 * @root: an interval tree
88
 *
89
 * Free a tree of MapInfo structures.
90
 * Since we allocated each MapInfo in one chunk, we need not consider the
91
 * contents and can simply free each RBNode.
92
 */
93

94
static void free_rbnode(RBNode *n)
95
{
96
    if (n) {
97
        free_rbnode(n->rb_left);
98
        free_rbnode(n->rb_right);
99
        g_free(n);
100
    }
101
}
102

103
void free_self_maps(IntervalTreeRoot *root)
104
{
105
    if (root) {
106
        free_rbnode(root->rb_root.rb_node);
107
        g_free(root);
108
    }
109
}
110