qemu/util/selfmap.c
Richard Henderson 53645dc4cb util/selfmap: Discard mapping on error
From clang-13:
util/selfmap.c:26:21: error: variable 'errors' set but not used \
    [-Werror,-Wunused-but-set-variable]

Quite right of course, but there's no reason not to check errors.

First, incrementing errors is incorrect, because qemu_strtoul
returns an errno not a count -- just or them together so that
we have a non-zero value at the end.

Second, if we have an error, do not add the struct to the list,
but free it instead.

Cc: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-07-26 07:06:49 -10:00

83 lines
2.2 KiB
C

/*
* Utility function to get QEMU's own process map
*
* Copyright (c) 2020 Linaro Ltd
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "qemu/osdep.h"
#include "qemu/cutils.h"
#include "qemu/selfmap.h"
GSList *read_self_maps(void)
{
gchar *maps;
GSList *map_info = NULL;
if (g_file_get_contents("/proc/self/maps", &maps, NULL, NULL)) {
gchar **lines = g_strsplit(maps, "\n", 0);
int i, entries = g_strv_length(lines);
for (i = 0; i < entries; i++) {
gchar **fields = g_strsplit(lines[i], " ", 6);
if (g_strv_length(fields) > 4) {
MapInfo *e = g_new0(MapInfo, 1);
int errors = 0;
const char *end;
errors |= qemu_strtoul(fields[0], &end, 16, &e->start);
errors |= qemu_strtoul(end + 1, NULL, 16, &e->end);
e->is_read = fields[1][0] == 'r';
e->is_write = fields[1][1] == 'w';
e->is_exec = fields[1][2] == 'x';
e->is_priv = fields[1][3] == 'p';
errors |= qemu_strtoul(fields[2], NULL, 16, &e->offset);
e->dev = g_strdup(fields[3]);
errors |= qemu_strtou64(fields[4], NULL, 10, &e->inode);
if (!errors) {
/*
* The last field may have leading spaces which we
* need to strip.
*/
if (g_strv_length(fields) == 6) {
e->path = g_strdup(g_strchug(fields[5]));
}
map_info = g_slist_prepend(map_info, e);
} else {
g_free(e->dev);
g_free(e);
}
}
g_strfreev(fields);
}
g_strfreev(lines);
g_free(maps);
}
/* ensure the map data is in the same order we collected it */
return g_slist_reverse(map_info);
}
/**
* free_self_maps:
* @info: a GSlist
*
* Free a list of MapInfo structures.
*/
static void free_info(gpointer data)
{
MapInfo *e = (MapInfo *) data;
g_free(e->dev);
g_free(e->path);
g_free(e);
}
void free_self_maps(GSList *info)
{
g_slist_free_full(info, &free_info);
}