Signed-off-by: Yeqi Fu <fufuyqqq...@gmail.com> --- include/qemu/envlist.h | 1 + linux-user/main.c | 23 +++++++++++++++++ util/envlist.c | 56 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 80 insertions(+)
diff --git a/include/qemu/envlist.h b/include/qemu/envlist.h index 6006dfae44..865eb18e17 100644 --- a/include/qemu/envlist.h +++ b/include/qemu/envlist.h @@ -7,6 +7,7 @@ envlist_t *envlist_create(void); void envlist_free(envlist_t *); int envlist_setenv(envlist_t *, const char *); int envlist_unsetenv(envlist_t *, const char *); +int envlist_appendenv(envlist_t *, const char *, const char *); int envlist_parse_set(envlist_t *, const char *); int envlist_parse_unset(envlist_t *, const char *); char **envlist_to_environ(const envlist_t *, size_t *); diff --git a/linux-user/main.c b/linux-user/main.c index 5e6b2e1714..313c116b3b 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -125,6 +125,8 @@ static void usage(int exitcode); static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX; const char *qemu_uname_release; +static const char *native_lib; + #if !defined(TARGET_DEFAULT_STACK_SIZE) /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so we allocate a bigger stack. Need a better solution, for example @@ -293,6 +295,13 @@ static void handle_arg_set_env(const char *arg) free(r); } +#if defined(CONFIG_USER_ONLY) && defined(CONFIG_USER_NATIVE_CALL) +static void handle_arg_native_bypass(const char *arg) +{ + native_lib = arg; +} +#endif + static void handle_arg_unset_env(const char *arg) { char *r, *p, *token; @@ -522,6 +531,10 @@ static const struct qemu_argument arg_table[] = { "", "Generate a /tmp/perf-${pid}.map file for perf"}, {"jitdump", "QEMU_JITDUMP", false, handle_arg_jitdump, "", "Generate a jit-${pid}.dump file for perf"}, +#if defined(CONFIG_USER_ONLY) && defined(CONFIG_USER_NATIVE_CALL) + {"native-bypass", "QEMU_NATIVE_BYPASS", true, handle_arg_native_bypass, + "", "native bypass for library calls in user mode only."}, +#endif {NULL, NULL, false, NULL, NULL, NULL} }; @@ -826,6 +839,16 @@ int main(int argc, char **argv, char **envp) } } + /* Set the library for native bypass */ + if (native_lib != NULL) { + char *token = malloc(strlen(native_lib) + 12); + strcpy(token, "LD_PRELOAD="); + strcat(token, native_lib); + if (envlist_appendenv(envlist, token, ":") != 0) { + usage(EXIT_FAILURE); + } + } + target_environ = envlist_to_environ(envlist, NULL); envlist_free(envlist); diff --git a/util/envlist.c b/util/envlist.c index db937c0427..713d52497e 100644 --- a/util/envlist.c +++ b/util/envlist.c @@ -201,6 +201,62 @@ envlist_unsetenv(envlist_t *envlist, const char *env) return (0); } +/* + * Appends environment value to envlist. If the environment + * variable already exists, the new value is appended to the + * existing one. + * + * Returns 0 in success, errno otherwise. + */ +int +envlist_appendenv(envlist_t *envlist, const char *env, const char *separator) +{ + struct envlist_entry *entry = NULL; + const char *eq_sign; + size_t envname_len; + + if ((envlist == NULL) || (env == NULL)) { + return (EINVAL); + } + + /* find out first equals sign in given env */ + eq_sign = strchr(env, '='); + if (eq_sign == NULL) { + return (EINVAL); + } + envname_len = eq_sign - env + 1; + + /* + * If there already exists variable with given name, + * we append the new value to the existing one. + */ + for (entry = envlist->el_entries.lh_first; entry != NULL; + entry = entry->ev_link.le_next) { + if (strncmp(entry->ev_var, env, envname_len) == 0) { + break; + } + } + + if (entry != NULL) { + char *new_env_value = NULL; + size_t new_env_len = strlen(entry->ev_var) + strlen(eq_sign) + + strlen(separator) + 1; + new_env_value = g_malloc(new_env_len); + strcpy(new_env_value, entry->ev_var); + strcat(new_env_value, separator); + strcat(new_env_value, eq_sign + 1); + g_free((char *)entry->ev_var); + entry->ev_var = new_env_value; + } else { + envlist->el_count++; + entry = g_malloc(sizeof(*entry)); + entry->ev_var = g_strdup(env); + QLIST_INSERT_HEAD(&envlist->el_entries, entry, ev_link); + } + + return (0); +} + /* * Returns given envlist as array of strings (in same form that * global variable environ is). Caller must free returned memory -- 2.34.1