summaryrefslogtreecommitdiff
path: root/src/shared/util.c
diff options
context:
space:
mode:
authorLennart Poettering <lennart@poettering.net>2015-03-23 18:55:36 +0700
committerLennart Poettering <lennart@poettering.net>2015-03-26 11:56:22 +0100
commit4034a06ddb82ec9868cd52496fef2f5faa25575f (patch)
treea832cd56abb7830985f3e7e9dff7451b96478c24 /src/shared/util.c
parentbe3ce3014eacd66fa292fc9e4e6b3d3b0ef7de23 (diff)
util: rework word parsing and c unescaping code
When parsing words from input files, optionally automatically unescape the passed strings, controllable via a new flags parameter. Make use of this in tmpfiles, and port everything else over, too. This improves parsing quite a bit, since we no longer have to process the same string multiple times with different calls, where an earlier call might corrupt the input for a later call.
Diffstat (limited to 'src/shared/util.c')
-rw-r--r--src/shared/util.c280
1 files changed, 168 insertions, 112 deletions
diff --git a/src/shared/util.c b/src/shared/util.c
index ad548da82a..8b76531d4f 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -1347,6 +1347,125 @@ char *cescape(const char *s) {
return r;
}
+static int cunescape_one(const char *p, size_t length, char *ret) {
+ int r = 1;
+
+ assert(p);
+ assert(*p);
+ assert(ret);
+
+ if (length != (size_t) -1 && length < 1)
+ return -EINVAL;
+
+ switch (p[0]) {
+
+ case 'a':
+ *ret = '\a';
+ break;
+ case 'b':
+ *ret = '\b';
+ break;
+ case 'f':
+ *ret = '\f';
+ break;
+ case 'n':
+ *ret = '\n';
+ break;
+ case 'r':
+ *ret = '\r';
+ break;
+ case 't':
+ *ret = '\t';
+ break;
+ case 'v':
+ *ret = '\v';
+ break;
+ case '\\':
+ *ret = '\\';
+ break;
+ case '"':
+ *ret = '"';
+ break;
+ case '\'':
+ *ret = '\'';
+ break;
+
+ case 's':
+ /* This is an extension of the XDG syntax files */
+ *ret = ' ';
+ break;
+
+ case 'x': {
+ /* hexadecimal encoding */
+ int a, b;
+
+ if (length != (size_t) -1 && length < 3)
+ return -EINVAL;
+
+ a = unhexchar(p[1]);
+ if (a < 0)
+ return -EINVAL;
+
+ b = unhexchar(p[2]);
+ if (b < 0)
+ return -EINVAL;
+
+ /* don't allow NUL bytes */
+ if (a == 0 && b == 0)
+ return -EINVAL;
+
+ *ret = (char) ((a << 4) | b);
+ r = 3;
+ break;
+ }
+
+ case '0':
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7': {
+ /* octal encoding */
+ int a, b, c, m;
+
+ if (length != (size_t) -1 && length < 4)
+ return -EINVAL;
+
+ a = unoctchar(p[0]);
+ if (a < 0)
+ return -EINVAL;
+
+ b = unoctchar(p[1]);
+ if (b < 0)
+ return -EINVAL;
+
+ c = unoctchar(p[2]);
+ if (c < 0)
+ return -EINVAL;
+
+ /* don't allow NUL bytes */
+ if (a == 0 && b == 0 && c == 0)
+ return -EINVAL;
+
+ /* Don't allow bytes above 255 */
+ m = (a << 6) | (b << 3) | c;
+ if (m > 255)
+ return -EINVAL;
+
+ *ret = (char) m;
+ r = 3;
+ break;
+ }
+
+ default:
+ return -EINVAL;
+ }
+
+ return r;
+}
+
char *cunescape_length_with_prefix(const char *s, size_t length, const char *prefix) {
char *r, *t;
const char *f;
@@ -1366,115 +1485,27 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre
memcpy(r, prefix, pl);
for (f = s, t = r + pl; f < s + length; f++) {
- size_t remaining = s + length - f;
+ size_t remaining;
+ int k;
+
+ remaining = s + length - f;
assert(remaining > 0);
- if (*f != '\\') { /* a literal literal */
+ if (*f != '\\' || remaining == 1) {
+ /* a literal literal, or a trailing backslash, copy verbatim */
*(t++) = *f;
continue;
}
- if (--remaining == 0) { /* copy trailing backslash verbatim */
- *(t++) = *f;
- break;
- }
-
- f++;
-
- switch (*f) {
-
- case 'a':
- *(t++) = '\a';
- break;
- case 'b':
- *(t++) = '\b';
- break;
- case 'f':
- *(t++) = '\f';
- break;
- case 'n':
- *(t++) = '\n';
- break;
- case 'r':
- *(t++) = '\r';
- break;
- case 't':
- *(t++) = '\t';
- break;
- case 'v':
- *(t++) = '\v';
- break;
- case '\\':
- *(t++) = '\\';
- break;
- case '"':
- *(t++) = '"';
- break;
- case '\'':
- *(t++) = '\'';
- break;
-
- case 's':
- /* This is an extension of the XDG syntax files */
- *(t++) = ' ';
- break;
-
- case 'x': {
- /* hexadecimal encoding */
- int a = -1, b = -1;
-
- if (remaining >= 2) {
- a = unhexchar(f[1]);
- b = unhexchar(f[2]);
- }
-
- if (a < 0 || b < 0 || (a == 0 && b == 0)) {
- /* Invalid escape code, let's take it literal then */
- *(t++) = '\\';
- *(t++) = 'x';
- } else {
- *(t++) = (char) ((a << 4) | b);
- f += 2;
- }
-
- break;
- }
-
- case '0':
- case '1':
- case '2':
- case '3':
- case '4':
- case '5':
- case '6':
- case '7': {
- /* octal encoding */
- int a = -1, b = -1, c = -1;
-
- if (remaining >= 3) {
- a = unoctchar(f[0]);
- b = unoctchar(f[1]);
- c = unoctchar(f[2]);
- }
-
- if (a < 0 || b < 0 || c < 0 || (a == 0 && b == 0 && c == 0)) {
- /* Invalid escape code, let's take it literal then */
- *(t++) = '\\';
- *(t++) = f[0];
- } else {
- *(t++) = (char) ((a << 6) | (b << 3) | c);
- f += 2;
- }
-
- break;
- }
-
- default:
+ k = cunescape_one(f + 1, remaining - 1, t);
+ if (k < 0) {
/* Invalid escape code, let's take it literal then */
*(t++) = '\\';
- *(t++) = *f;
- break;
+ continue;
}
+
+ f += k;
+ t++;
}
*t = 0;
@@ -3411,7 +3442,7 @@ char **replace_env_argv(char **argv, char **env) {
if (e) {
int r;
- r = strv_split_quoted(&m, e, true);
+ r = strv_split_quoted(&m, e, UNQUOTE_RELAX);
if (r < 0) {
ret[k] = NULL;
strv_free(ret);
@@ -6382,7 +6413,7 @@ int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value)) {
_cleanup_free_ char *word = NULL;
char *value = NULL;
- r = unquote_first_word(&p, &word, true);
+ r = unquote_first_word(&p, &word, UNQUOTE_RELAX);
if (r < 0)
return r;
if (r == 0)
@@ -6422,7 +6453,7 @@ int get_proc_cmdline_key(const char *key, char **value) {
_cleanup_free_ char *word = NULL;
const char *e;
- r = unquote_first_word(&p, &word, true);
+ r = unquote_first_word(&p, &word, UNQUOTE_RELAX);
if (r < 0)
return r;
if (r == 0)
@@ -7275,9 +7306,10 @@ int is_dir(const char* path, bool follow) {
return !!S_ISDIR(st.st_mode);
}
-int unquote_first_word(const char **p, char **ret, bool relax) {
+int unquote_first_word(const char **p, char **ret, UnquoteFlags flags) {
_cleanup_free_ char *s = NULL;
size_t allocated = 0, sz = 0;
+ int r;
enum {
START,
@@ -7335,7 +7367,7 @@ int unquote_first_word(const char **p, char **ret, bool relax) {
case VALUE_ESCAPE:
if (c == 0) {
- if (relax)
+ if (flags & UNQUOTE_RELAX)
goto finish;
return -EINVAL;
}
@@ -7343,6 +7375,14 @@ int unquote_first_word(const char **p, char **ret, bool relax) {
if (!GREEDY_REALLOC(s, allocated, sz+2))
return -ENOMEM;
+ if (flags & UNQUOTE_CUNESCAPE) {
+ r = cunescape_one(*p, (size_t) -1, &c);
+ if (r < 0)
+ return -EINVAL;
+
+ (*p) += r - 1;
+ }
+
s[sz++] = c;
state = VALUE;
@@ -7350,7 +7390,7 @@ int unquote_first_word(const char **p, char **ret, bool relax) {
case SINGLE_QUOTE:
if (c == 0) {
- if (relax)
+ if (flags & UNQUOTE_RELAX)
goto finish;
return -EINVAL;
} else if (c == '\'')
@@ -7368,7 +7408,7 @@ int unquote_first_word(const char **p, char **ret, bool relax) {
case SINGLE_QUOTE_ESCAPE:
if (c == 0) {
- if (relax)
+ if (flags & UNQUOTE_RELAX)
goto finish;
return -EINVAL;
}
@@ -7376,6 +7416,14 @@ int unquote_first_word(const char **p, char **ret, bool relax) {
if (!GREEDY_REALLOC(s, allocated, sz+2))
return -ENOMEM;
+ if (flags & UNQUOTE_CUNESCAPE) {
+ r = cunescape_one(*p, (size_t) -1, &c);
+ if (r < 0)
+ return -EINVAL;
+
+ (*p) += r - 1;
+ }
+
s[sz++] = c;
state = SINGLE_QUOTE;
break;
@@ -7398,7 +7446,7 @@ int unquote_first_word(const char **p, char **ret, bool relax) {
case DOUBLE_QUOTE_ESCAPE:
if (c == 0) {
- if (relax)
+ if (flags & UNQUOTE_RELAX)
goto finish;
return -EINVAL;
}
@@ -7406,6 +7454,14 @@ int unquote_first_word(const char **p, char **ret, bool relax) {
if (!GREEDY_REALLOC(s, allocated, sz+2))
return -ENOMEM;
+ if (flags & UNQUOTE_CUNESCAPE) {
+ r = cunescape_one(*p, (size_t) -1, &c);
+ if (r < 0)
+ return -EINVAL;
+
+ (*p) += r - 1;
+ }
+
s[sz++] = c;
state = DOUBLE_QUOTE;
break;
@@ -7435,7 +7491,7 @@ finish:
return 1;
}
-int unquote_many_words(const char **p, ...) {
+int unquote_many_words(const char **p, UnquoteFlags flags, ...) {
va_list ap;
char **l;
int n = 0, i, c, r;
@@ -7446,7 +7502,7 @@ int unquote_many_words(const char **p, ...) {
assert(p);
/* Count how many words are expected */
- va_start(ap, p);
+ va_start(ap, flags);
for (;;) {
if (!va_arg(ap, char **))
break;
@@ -7461,7 +7517,7 @@ int unquote_many_words(const char **p, ...) {
l = newa0(char*, n);
for (c = 0; c < n; c++) {
- r = unquote_first_word(p, &l[c], false);
+ r = unquote_first_word(p, &l[c], flags);
if (r < 0) {
int j;
@@ -7477,7 +7533,7 @@ int unquote_many_words(const char **p, ...) {
/* If we managed to parse all words, return them in the passed
* in parameters */
- va_start(ap, p);
+ va_start(ap, flags);
for (i = 0; i < n; i++) {
char **v;