From 6cc2387e1a6b4762931b587a114d21ee2d22399b Mon Sep 17 00:00:00 2001
From: Nick Wellnhofer <wellnhofer@aevum.de>
Date: Wed, 24 Jul 2024 11:42:39 +0200
Subject: [PATCH] shell: Only use readline on terminals

Should fix xmllint shell tests.
---
 shell.c      | 52 ++++++++++++++++++++++++++++++++--------------------
 xmlcatalog.c | 50 +++++++++++++++++++++++++++++---------------------
 2 files changed, 61 insertions(+), 41 deletions(-)

diff --git a/shell.c b/shell.c
index 6a21898d..a1572b28 100644
--- a/shell.c
+++ b/shell.c
@@ -12,6 +12,12 @@
 #include <stdlib.h>
 #include <string.h>
 
+#ifdef _WIN32
+  #include <io.h>
+#else
+  #include <unistd.h>
+#endif
+
 #ifdef HAVE_LIBREADLINE
 #include <readline/readline.h>
 #ifdef HAVE_LIBHISTORY
@@ -31,6 +37,10 @@
 
 #include "private/shell.h"
 
+#ifndef STDIN_FILENO
+  #define STDIN_FILENO 0
+#endif
+
 /*
  * TODO: Improvement/cleanups for the XML shell
  *     - allow to shell out an editor on a subpart
@@ -1047,37 +1057,39 @@ xmllintShellPwd(xmllintShellCtxtPtr ctxt ATTRIBUTE_UNUSED, char *buffer,
  */
 static char *
 xmllintShellReadline(char *prompt) {
-#ifdef HAVE_LIBREADLINE
-    char *line_read;
-
-    /* Get a line from the user. */
-    line_read = readline (prompt);
-
-#ifdef HAVE_LIBHISTORY
-    /* If the line has any text in it, save it on the history. */
-    if (line_read && *line_read)
-       add_history (line_read);
-#endif
-
-    return (line_read);
-#else
-    char line_read[501];
+    char buf[501];
     char *ret;
     int len;
 
+#ifdef HAVE_LIBREADLINE
+    if (isatty(STDIN_FILENO)) {
+        char *line_read;
+
+        /* Get a line from the user. */
+        line_read = readline (prompt);
+
+#ifdef HAVE_LIBHISTORY
+        /* If the line has any text in it, save it on the history. */
+        if (line_read && *line_read)
+           add_history (line_read);
+#endif
+
+        return (line_read);
+    }
+#endif
+
     if (prompt != NULL)
        fprintf(stdout, "%s", prompt);
     fflush(stdout);
-    if (!fgets(line_read, 500, stdin))
+    if (!fgets(buf, 500, stdin))
         return(NULL);
-    line_read[500] = 0;
-    len = strlen(line_read);
+    buf[500] = 0;
+    len = strlen(buf);
     ret = (char *) malloc(len + 1);
     if (ret != NULL) {
-       memcpy (ret, line_read, len + 1);
+       memcpy (ret, buf, len + 1);
     }
     return(ret);
-#endif
 }
 
 /**
diff --git a/xmlcatalog.c b/xmlcatalog.c
index a1cd9870..ac4b80aa 100644
--- a/xmlcatalog.c
+++ b/xmlcatalog.c
@@ -16,6 +16,8 @@
 #ifdef _WIN32
   #include <fcntl.h>
   #include <io.h>
+#else
+  #include <unistd.h>
 #endif
 
 #ifdef HAVE_LIBREADLINE
@@ -30,6 +32,10 @@
 #include <libxml/catalog.h>
 #include <libxml/parser.h>
 
+#ifndef STDIN_FILENO
+  #define STDIN_FILENO 0
+#endif
+
 #if defined(LIBXML_CATALOG_ENABLED) && defined(LIBXML_OUTPUT_ENABLED)
 static int shell = 0;
 static int sgml = 0;
@@ -63,37 +69,39 @@ static char *filename = NULL;
  */
 static char *
 xmlShellReadline(const char *prompt) {
-#ifdef HAVE_LIBREADLINE
-    char *line_read;
-
-    /* Get a line from the user. */
-    line_read = readline (prompt);
-
-#ifdef HAVE_LIBHISTORY
-    /* If the line has any text in it, save it on the history. */
-    if (line_read && *line_read)
-	add_history (line_read);
-#endif
-
-    return (line_read);
-#else
-    char line_read[501];
+    char buf[501];
     char *ret;
     int len;
 
+#ifdef HAVE_LIBREADLINE
+    if (isatty(STDIN_FILENO)) {
+        char *line_read;
+
+        /* Get a line from the user. */
+        line_read = readline (prompt);
+
+#ifdef HAVE_LIBHISTORY
+        /* If the line has any text in it, save it on the history. */
+        if (line_read && *line_read)
+           add_history (line_read);
+#endif
+
+        return (line_read);
+    }
+#endif
+
     if (prompt != NULL)
-	fprintf(stdout, "%s", prompt);
+       fprintf(stdout, "%s", prompt);
     fflush(stdout);
-    if (!fgets(line_read, 500, stdin))
+    if (!fgets(buf, 500, stdin))
         return(NULL);
-    line_read[500] = 0;
-    len = strlen(line_read);
+    buf[500] = 0;
+    len = strlen(buf);
     ret = (char *) malloc(len + 1);
     if (ret != NULL) {
-	memcpy (ret, line_read, len + 1);
+       memcpy (ret, buf, len + 1);
     }
     return(ret);
-#endif
 }
 
 static void usershell(void) {