aio: add support for gets ?-eol <eolstr>? ?-keep 0|1?

This can make it easier to read non-newline based protocols
with gets, especially in conjunction with timeout.

Signed-off-by: Steve Bennett <steveb@workware.net.au>

Author: msteveb

jim-aio.c

@@ -1127,15 +1127,61 @@ static int aio_cmd_copy(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
     return JIM_OK;
 }
 
+/* Like strstr() but optimised in the case the the needle is of length 1 */
+static const char *jim_strstr(const char *haystack, int haylen, const char *needle, int needlen)
+{
+    if (needlen == 1) {
+        return (const char *)memchr(haystack, needle[0], strlen(haystack));
+    }
+    return strstr(haystack, needle);
+}
+
 static int aio_cmd_gets(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
 {
     AioFile *af = Jim_CmdPrivData(interp);
     Jim_Obj *objPtr = NULL;
     int len;
     int nb;
     unsigned flags = AIO_ONEREAD;
-    char *nl = NULL;
+    const char *nl = NULL;
     int offset = 0;
+    long keepnl = 0;
+    const char *nlstr = "\n";
+    int nlstrlen = 1;
+
+    while (argc >= 2) {
+        enum {OPT_EOL, OPT_KEEP};
+        static const char * const options[] = {
+            "-eol",
+            "-keep",
+            NULL
+        };
+        int opt;
+
+        if (Jim_GetEnum(interp, argv[0], options, &opt, NULL, JIM_ERRMSG | JIM_ENUM_ABBREV) != JIM_OK) {
+            return JIM_ERR;
+        }
+
+        switch (opt) {
+            case OPT_EOL:
+                nlstr = Jim_GetString(argv[1], &nlstrlen);
+                break;
+
+            case OPT_KEEP:
+                if (Jim_GetLong(interp, argv[1], &keepnl) != JIM_OK) {
+                    return JIM_ERR;
+                }
+                break;
+            default:
+                return JIM_ERR;
+        }
+        argc -= 2;
+        argv += 2;
+    }
+
+    if (argc > 1) {
+        return JIM_USAGE;
+    }
 
     errno = 0;
 
@@ -1148,10 +1194,10 @@ static int aio_cmd_gets(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
     while (!aio_eof(af)) {
         if (af->readbuf) {
             const char *pt = Jim_GetString(af->readbuf, &len);
-            nl = memchr(pt + offset, '\n', len - offset);
+            nl = jim_strstr(pt + offset, len - offset, nlstr, nlstrlen);
             if (nl) {
                 /* got a line */
-                objPtr = Jim_NewStringObj(interp, pt, nl - pt);
+                objPtr = Jim_NewStringObj(interp, pt, nl - pt + (keepnl ? nlstrlen : 0));
                 /* And consume it plus the newline */
                 aio_consume(af->readbuf, nl - pt + 1);
                 break;
@@ -2169,10 +2215,10 @@ static const jim_subcmd_type aio_command_table[] = {
         /* Description: Internal command to return the taint of the channel. */
     },
     {   "gets",
-        "?var?",
+        "?-eol <str>? ?-keep 0|1? ?var?",
         aio_cmd_gets,
         0,
-        1,
+        -1,
         /* Description: Read one line and return it or store it in the var */
     },
     {   "puts",

tests/aio.test

@@ -98,6 +98,61 @@ test aio-4.1 {gets invalid var} -body {
 	$f gets badvar(abc)
 } -returnCodes error -result {can't set "badvar(abc)": variable isn't array}
 
+test aio-4.2 {gets -eol} -body {
+	set ff [open copy.in]
+	set rc [$ff gets -eol 2 buf]
+	$ff close
+	list $rc $buf
+} -result {10 {line1
+line}}
+
+test aio-4.3 {gets -keep} -body {
+	set ff [open copy.in]
+	set rc [$ff gets -keep 1 buf]
+	$ff close
+	list $rc $buf
+} -result {6 {line1
+}}
+
+test aio-4.4 {gets -eol -keep} -body {
+	set ff [open copy.in]
+	set rc [$ff gets -keep 1 -eol 2 buf]
+	$ff close
+	list $rc $buf
+} -result {11 {line1
+line2}}
+
+test aio-4.5 {gets -eol -keep chars} -body {
+	set ff [open copy.in]
+	set rc [$ff gets -eol ne2 -keep 1 buf]
+	$ff close
+	list $rc $buf
+} -result {11 {line1
+line2}}
+
+test aio-4.6 {gets -eol no var} -body {
+	set ff [open copy.in]
+	set buf [$ff gets -eol ne2 -keep 1]
+	$ff close
+	set buf
+} -result {line1
+line2}
+
+test aio-4.7 {gets -keep 0 count} -body {
+	set ff [open copy.in]
+	set count [$ff gets -keep 0 buf]
+	$ff close
+	list $count $buf
+} -result {5 line1}
+
+test aio-4.8 {gets -keep 1 count} -body {
+	set ff [open copy.in]
+	set count [$ff gets -keep 1 buf]
+	$ff close
+	list $count $buf
+} -result {6 {line1
+}}
+
 test aio-5.1 {puts usage} -body {
 	stdout puts -badopt abc
 } -returnCodes error -result {wrong # args: should be "stdout puts ?-nonewline? str"}