[libvirt] [PATCH 4/8] virsh: add vrshCommandParser abstraction
add vrshCommandParser and make vshCommandParse() accepts different
parsers.
the current code for parse command string is integrated as
vshCommandStringParse().
Signed-off-by: Lai Jiangshan la...@cn.fujitsu.com
---
virsh.c | 91 +++-
1 file changed, 45 insertions(+), 46 deletions(-)
diff --git a/tools/virsh.c b/tools/virsh.c
index f97ee42..27321a5 100644
--- a/tools/virsh.c
+++ b/tools/virsh.c
@@ -10158,23 +10158,29 @@ vshCommandRun(vshControl *ctl, const vshCmd *cmd)
return ret;
}
+#define VSH_TK_ERROR -1
+#define VSH_TK_ARG 0
+#define VSH_TK_SUBCMD_END 1
+#define VSH_TK_END 2
+
+typedef struct __vshCommandParser {
+int (*getNextArg)(vshControl *, struct __vshCommandParser *, char **);
+char *pos;
+} vshCommandParser;
+
+static int vshCommandParse(vshControl *ctl, vshCommandParser *parser);
+
/* ---
* Command string parsing
* ---
*/
-#define VSH_TK_ERROR-1
-#define VSH_TK_NONE0
-#define VSH_TK_DATA1
-#define VSH_TK_END2
static int
-vshCommandGetToken(vshControl *ctl, char *str, char **end, char **res)
+vshCommandStringGetArg(vshControl *ctl, vshCommandParser *parser, char **res)
{
bool double_quote = false;
int sz = 0;
-char *p = str, *q;
-
-*end = NULL;
+char *p = parser-pos, *q;
while (p *p (*p == ' ' || *p == '\t'))
p++;
@@ -10182,8 +10188,8 @@ vshCommandGetToken(vshControl *ctl, char *str, char
**end, char **res)
if (p == NULL || *p == '\0')
return VSH_TK_END;
if (*p == ';') {
-*end = ++p; /* = \0 or begin of next command */
-return VSH_TK_END;
+parser-pos = ++p; /* = \0 or begin of next command */
+return VSH_TK_SUBCMD_END;
}
q = p;
@@ -10218,14 +10224,25 @@ copy:
}
*(*res + sz) = '\0';
-*end = p;
-return VSH_TK_DATA;
+parser-pos = p;
+return VSH_TK_ARG;
+}
+
+static int vshCommandStringParse(vshControl *ctl, char *cmdstr)
+{
+vshCommandParser parser;
+
+if (cmdstr == NULL || *cmdstr == '\0')
+return FALSE;
+
+parser.pos = cmdstr;
+parser.getNextArg = vshCommandStringGetArg;
+return vshCommandParse(ctl, parser);
}
static int
-vshCommandParse(vshControl *ctl, char *cmdstr)
+vshCommandParse(vshControl *ctl, vshCommandParser *parser)
{
-char *str;
char *tkdata = NULL;
vshCmd *clast = NULL;
vshCmdOpt *first = NULL;
@@ -10235,44 +10252,27 @@ vshCommandParse(vshControl *ctl, char *cmdstr)
ctl-cmd = NULL;
}
-if (cmdstr == NULL || *cmdstr == '\0')
-return FALSE;
-
-str = cmdstr;
-while (str *str) {
+for (;;) {
vshCmdOpt *last = NULL;
const vshCmdDef *cmd = NULL;
-int tk = VSH_TK_NONE;
+int tk;
int data_ct = 0;
first = NULL;
-while (tk != VSH_TK_END) {
-char *end = NULL;
+for (;;) {
const vshCmdOptDef *opt = NULL;
tkdata = NULL;
+tk = parser-getNextArg(ctl, parser, tkdata);
-/* get token */
-tk = vshCommandGetToken(ctl, str, end, tkdata);
-
-str = end;
-
-if (tk == VSH_TK_END) {
-VIR_FREE(tkdata);
-break;
-}
if (tk == VSH_TK_ERROR)
goto syntaxError;
+if (tk != VSH_TK_ARG)
+break;
if (cmd == NULL) {
/* first token must be command name */
-if (tk != VSH_TK_DATA) {
-vshError(ctl,
- _(unexpected token (command name): '%s'),
- tkdata);
-goto syntaxError;
-}
if (!(cmd = vshCmddefSearch(tkdata))) {
vshError(ctl, _(unknown command: '%s'), tkdata);
goto syntaxError; /* ... or ignore this command only? */
@@ -10299,11 +10299,10 @@ vshCommandParse(vshControl *ctl, char *cmdstr)
if (optstr)
tkdata = optstr;
else
-tk = vshCommandGetToken(ctl, str, end, tkdata);
-str = end;
+tk = parser-getNextArg(ctl, parser, tkdata);
if (tk == VSH_TK_ERROR)
goto syntaxError;
-if (tk != VSH_TK_DATA) {
+if (tk != VSH_TK_ARG) {
vshError(ctl,
_(expected syntax: --%s %s),
opt-name,
@@ -10320,7 +10319,7 @@ vshCommandParse(vshControl *ctl, char *cmdstr)
goto syntaxError;
}
}
-} else if (tk == VSH_TK_DATA) {
+} else {
if (!(opt = vshCmddefGetData(cmd,
Re: [libvirt] [PATCH 4/8] virsh: add vrshCommandParser abstraction
On 10/12/2010 01:13 AM, Lai Jiangshan wrote:
add vrshCommandParser and make vshCommandParse() accepts different
s/vrsh/vsh/; s/accepts/accept/
parsers.
the current code for parse command string is integrated as
vshCommandStringParse().
Signed-off-by: Lai Jiangshanla...@cn.fujitsu.com
---
virsh.c | 91
+++-
1 file changed, 45 insertions(+), 46 deletions(-)
diff --git a/tools/virsh.c b/tools/virsh.c
index f97ee42..27321a5 100644
--- a/tools/virsh.c
+++ b/tools/virsh.c
@@ -10158,23 +10158,29 @@ vshCommandRun(vshControl *ctl, const vshCmd *cmd)
return ret;
}
+#define VSH_TK_ERROR -1
+#define VSH_TK_ARG 0
+#define VSH_TK_SUBCMD_END 1
+#define VSH_TK_END 2
Hmm, in addition to floating this earlier, you also lost _NONE and added
_SUBCMD_END. The enum I suggested in patch 3 is sounding more
appealing, so I'll squash it in now.
+
+typedef struct __vshCommandParser {
+int (*getNextArg)(vshControl *, struct __vshCommandParser *, char **);
+char *pos;
+} vshCommandParser;
+
+static int vshCommandParse(vshControl *ctl, vshCommandParser *parser);
I'm a fan of avoiding forward static declarations if the file can be
rearranged topologically.
+
/* ---
* Command string parsing
* ---
*/
This logically belongs before enums related to command parsing.
-#define VSH_TK_ERROR-1
-#define VSH_TK_NONE0
-#define VSH_TK_DATA1
-#define VSH_TK_END2
static int
-vshCommandGetToken(vshControl *ctl, char *str, char **end, char **res)
+vshCommandStringGetArg(vshControl *ctl, vshCommandParser *parser, char **res)
{
bool double_quote = false;
int sz = 0;
-char *p = str, *q;
-
-*end = NULL;
+char *p = parser-pos, *q;
Rebasing this on top of my edits to patch 1 is getting interesting.
while (p *p (*p == ' ' || *p == '\t'))
You no longer need to check if p is NULL,
+static int vshCommandStringParse(vshControl *ctl, char *cmdstr)
+{
+vshCommandParser parser;
+
+if (cmdstr == NULL || *cmdstr == '\0')
+return FALSE;
+
+parser.pos = cmdstr;
...since this guarantees it is non-NULL.
+for (;;) {
$ git grep 'for.*;;' | wc -l
14
$ git grep 'while.*true' | wc -l
6
$ git grep 'while.*1' | wc -l
70
Guess which one I'm changing this to, for consistency :)
ACK, with those nits fixed. Here's what I squashed in:
diff --git i/tools/virsh.c w/tools/virsh.c
index 56985a4..d9f72f3 100644
--- i/tools/virsh.c
+++ w/tools/virsh.c
@@ -10174,38 +10174,40 @@ vshCommandRun(vshControl *ctl, const vshCmd *cmd)
return ret;
}
-#define VSH_TK_ERROR -1
-#define VSH_TK_ARG 0
-#define VSH_TK_SUBCMD_END 1
-#define VSH_TK_END 2
+/* ---
+ * Command string parsing
+ * ---
+ */
+
+typedef enum {
+VSH_TK_ERROR, /* Failed to parse a token */
+VSH_TK_ARG, /* Arbitrary argument, might be option or empty */
+VSH_TK_SUBCMD_END, /* Separation between commands */
+VSH_TK_END /* No more commands */
+} vshCommandToken;
typedef struct __vshCommandParser {
-int (*getNextArg)(vshControl *, struct __vshCommandParser *, char **);
+vshCommandToken (*getNextArg)(vshControl *, struct
__vshCommandParser *,
+ char **);
char *pos;
} vshCommandParser;
static int vshCommandParse(vshControl *ctl, vshCommandParser *parser);
-/* ---
- * Command string parsing
- * ---
- */
-
-static int ATTRIBUTE_NONNULL(2) ATTRIBUTE_NONNULL(3)
+static vshCommandToken ATTRIBUTE_NONNULL(2) ATTRIBUTE_NONNULL(3)
vshCommandStringGetArg(vshControl *ctl, vshCommandParser *parser, char
**res)
{
bool double_quote = false;
int sz = 0;
char *p = parser-pos;
-char *q = vshStrdup(ctl, str);
+char *q = vshStrdup(ctl, p);
-*end = NULL;
*res = q;
-while (p *p (*p == ' ' || *p == '\t'))
+while (*p (*p == ' ' || *p == '\t'))
p++;
-if (p == NULL || *p == '\0')
+if (*p == '\0')
return VSH_TK_END;
if (*p == ';') {
parser-pos = ++p; /* = \0 or begin of next command */
@@ -10261,15 +10262,15 @@ vshCommandParse(vshControl *ctl,
vshCommandParser *parser)
ctl-cmd = NULL;
}
-for (;;) {
+while (1) {
vshCmdOpt *last = NULL;
const vshCmdDef *cmd = NULL;
-int tk;
+vshCommandToken tk;
int data_ct = 0;
first = NULL;
-for (;;) {
+while (1) {
const vshCmdOptDef *opt = NULL;
tkdata = NULL;
--
Eric Blake ebl...@redhat.com+1-801-349-2682
Libvirt virtualization library http://libvirt.org
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