imap4d: implement SEARCH CHARSET; fix BODY and TEXT searches.

* imap4d/search.c: Implement proper BODY searches. Implement CHARSET.
* imap4d/util.c (util_strcasestr): Remove. Use mu_c_strcasestr instead.
* imap4d/imap4d.h: Likewise.
* NEWS: Document changes.

5 files changed, 341 insertions, 141 deletions

diff --git a/NEWS b/NEWS
index 84d36010c..4f5c0dec9 100644
--- a/NEWS
+++ b/NEWS
@@ -1,2 +1,2 @@
-GNU mailutils NEWS -- history of user-visible changes. 2019-01-23
+GNU mailutils NEWS -- history of user-visible changes. 2019-01-26
 Copyright (C) 2002-2019 Free Software Foundation, Inc.
@@ -8,2 +8,11 @@ Version 3.5.90 (git)
 
+* imap4d: SEARCH command
+
+** Implemented SEARCH CHARSET
+
+** Improved SEARCH BODY and SEARCH TEXT commands
+
+Both commands now properly descend into multipart message parts and
+decode messages, if necessary
+
 * Fixes in the 'mail' utility
diff --git a/imap4d/imap4d.h b/imap4d/imap4d.h
index 2ad339a30..b90d653a0 100644
--- a/imap4d/imap4d.h
+++ b/imap4d/imap4d.h
@@ -456,3 +456,2 @@ extern int util_parse_ctime_date (const char *date, time_t *timep,
                                   enum datetime_parse_mode flag);
-extern char *util_strcasestr (const char *haystack, const char *needle);
 extern char *util_localname (void);
diff --git a/imap4d/search.c b/imap4d/search.c
index 1d28b570f..3c243eddf 100644
--- a/imap4d/search.c
+++ b/imap4d/search.c
@@ -17,2 +17,3 @@
 #include "imap4d.h"
+#include <mailutils/assoc.h>
 
@@ -92,3 +93,3 @@ struct search_node
 static void cond_msgset (struct parsebuf *, struct search_node *,
-                         struct value *, struct value *);       
+                         struct value *, struct value *);
 static void cond_bcc (struct parsebuf *, struct search_node *,
@@ -96,21 +97,21 @@ static void cond_bcc (struct parsebuf *, struct search_node *,
 static void cond_before (struct parsebuf *, struct search_node *,
-                         struct value *, struct value *);     
+                         struct value *, struct value *);
 static void cond_body (struct parsebuf *, struct search_node *,
-                       struct value *, struct value *);       
+                       struct value *, struct value *);
 static void cond_cc (struct parsebuf *, struct search_node *,
-                     struct value *, struct value *);        
+                     struct value *, struct value *);
 static void cond_from (struct parsebuf *, struct search_node *,
-                       struct value *, struct value *);     
+                       struct value *, struct value *);
 static void cond_header (struct parsebuf *, struct search_node *,
-                         struct value *, struct value *);      
+                         struct value *, struct value *);
 static void cond_keyword (struct parsebuf *, struct search_node *,
-                          struct value *, struct value *);   
+                          struct value *, struct value *);
 static void cond_larger (struct parsebuf *, struct search_node *,
-                         struct value *, struct value *);   
+                         struct value *, struct value *);
 static void cond_on (struct parsebuf *, struct search_node *,
-                     struct value *, struct value *);         
+                     struct value *, struct value *);
 static void cond_sentbefore (struct parsebuf *, struct search_node *,
-                             struct value *, struct value *); 
+                             struct value *, struct value *);
 static void cond_senton (struct parsebuf *, struct search_node *,
-                         struct value *, struct value *);     
+                         struct value *, struct value *);
 static void cond_sentsince (struct parsebuf *, struct search_node *,
@@ -118,13 +119,13 @@ static void cond_sentsince (struct parsebuf *, struct search_node *,
 static void cond_since (struct parsebuf *, struct search_node *,
-                        struct value *, struct value *);      
+                        struct value *, struct value *);
 static void cond_smaller (struct parsebuf *, struct search_node *,
-                          struct value *, struct value *);    
+                          struct value *, struct value *);
 static void cond_subject (struct parsebuf *, struct search_node *,
-                          struct value *, struct value *);  
+                          struct value *, struct value *);
 static void cond_text (struct parsebuf *, struct search_node *,
-                       struct value *, struct value *);       
+                       struct value *, struct value *);
 static void cond_to (struct parsebuf *, struct search_node *,
-                     struct value *, struct value *);      
+                     struct value *, struct value *);
 static void cond_uid (struct parsebuf *, struct search_node *,
-                      struct value *, struct value *);   
+                      struct value *, struct value *);
 
@@ -140,3 +141,3 @@ struct cond
 /* Types are: s -- string
-              n -- number
+              n -- number
               d -- date
@@ -215,3 +216,3 @@ struct mem_chain
    that they are enclosed in doublequotes */
-#define MAXTOKEN 64 
+#define MAXTOKEN 64
 
@@ -220,14 +221,15 @@ struct parsebuf
 {
-  imap4d_tokbuf_t tok;          /* Token buffer */   
+  imap4d_tokbuf_t tok;          /* Token buffer */
   int arg;                      /* Argument number */
   char *token;                  /* Current token */
-  int isuid;                    /* UIDs instead of msgnos are required */ 
+  int isuid;                    /* UIDs instead of msgnos are required */
   char *err_mesg;               /* Error message if a parse error occured */
   struct mem_chain *alloc;      /* Chain of objects allocated during parsing */
-  
+  char *charset;                /* Charset, other than US-ASCII requested */
+
   struct search_node *tree;     /* Parse tree */
-  
-                                /* Execution time only: */
+
+                                /* Execution time only: */
   size_t msgno;                 /* Number of current message */
-  mu_message_t msg;             /* Current message */ 
+  mu_message_t msg;             /* Current message */
 };
@@ -243,2 +245,3 @@ static int search_run (struct parsebuf *pb);
 static void do_search (struct parsebuf *pb);
+static int available_charset (const char *charset);
 
@@ -248,3 +251,3 @@ static void do_search (struct parsebuf *pb);
    Arguments:  OPTIONAL [CHARSET] specification
-               searching criteria (one or more)
+               searching criteria (one or more)
 
@@ -253,5 +256,5 @@ static void do_search (struct parsebuf *pb);
    Result:     OK - search completed
-               NO - search error: can't search that [CHARSET] or
-                    criteria
-               BAD - command unknown or arguments invalid
+               NO - search error: can't search that [CHARSET] or
+                    criteria
+               BAD - command unknown or arguments invalid
 */
@@ -260,3 +263,3 @@ int
 imap4d_search (struct imap4d_session *session,
-               struct imap4d_command *command, imap4d_tokbuf_t tok)
+               struct imap4d_command *command, imap4d_tokbuf_t tok)
 {
@@ -264,3 +267,3 @@ imap4d_search (struct imap4d_session *session,
   char *err_text= "";
-  
+
   rc = imap4d_search0 (tok, 0, &err_text);
@@ -268,3 +271,3 @@ imap4d_search (struct imap4d_session *session,
 }
-  
+
 int
@@ -273,3 +276,3 @@ imap4d_search0 (imap4d_tokbuf_t tok, int isuid, char **err_text)
   struct parsebuf parsebuf;
-  
+
   memset (&parsebuf, 0, sizeof(parsebuf));
@@ -286,3 +289,3 @@ imap4d_search0 (imap4d_tokbuf_t tok, int isuid, char **err_text)
     }
-  
+
   if (mu_c_strcasecmp (parsebuf.token, "CHARSET") == 0)
@@ -298,5 +301,11 @@ imap4d_search0 (imap4d_tokbuf_t tok, int isuid, char **err_text)
         {
-          *err_text = "Charset not supported";
-          return RESP_NO;
+          parsebuf.charset = parse_strdup (&parsebuf, parsebuf.token);
+          if (!available_charset (parsebuf.charset))
+            {
+              *err_text = "[BADCHARSET] Charset not supported";
+              return RESP_NO;
+            }
         }
+      else
+        parsebuf.charset = NULL;
 
@@ -307,3 +316,2 @@ imap4d_search0 (imap4d_tokbuf_t tok, int isuid, char **err_text)
         }
-
     }
@@ -325,8 +333,8 @@ imap4d_search0 (imap4d_tokbuf_t tok, int isuid, char **err_text)
     }
-  
+
   /* Execute compiled expression */
   do_search (&parsebuf);
-  
+
   parse_free_mem (&parsebuf);
-  
+
   *err_text = "Completed";
@@ -341,3 +349,3 @@ do_search (struct parsebuf *pb)
   size_t count = 0;
-  
+
   mu_mailbox_messages_count (mbox, &count);
@@ -419,3 +427,3 @@ parse_alloc (struct parsebuf *pb, size_t size)
 
-/* Create a copy of the string. */ 
+/* Create a copy of the string. */
 char *
@@ -447,3 +455,3 @@ parse_msgset_create (struct parsebuf *pb, mu_mailbox_t mbox, int flags)
    search_key_list : search_key
-                   | search_key_list search_key
+                   | search_key_list search_key
                    ;
@@ -451,3 +459,3 @@ parse_msgset_create (struct parsebuf *pb, mu_mailbox_t mbox, int flags)
    search_key      : simple_key
-                   | NOT simple_key
+                   | NOT simple_key
                    | OR simple_key simple_key
@@ -488,3 +496,3 @@ parse_search_key (struct parsebuf *pb)