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[mandoc.git] / roff_escape.c

diff --git a/roff_escape.c b/roff_escape.c
index 333e0e3fe47094da9b49b49ac3a4e231d0ad298f..b1a4fbeb40ef035572eea2eb7f582120da7bd949 100644 (file)
--- a/roff_escape.c
+++ b/roff_escape.c
@@ -1,4 +1,4 @@
-/* $Id: roff_escape.c,v 1.13 2022/06/07 09:54:40 schwarze Exp $ */
+/* $Id: roff_escape.c,v 1.14 2022/06/08 13:23:57 schwarze Exp $ */
 /*
  * Copyright (c) 2011, 2012, 2013, 2014, 2015, 2017, 2018, 2020, 2022
  *               Ingo Schwarze <schwarze@openbsd.org>
@@ -59,7 +59,7 @@ mandoc_escape(const char **rendarg, const char **rarg, int *rargl)
  * sequence are returned in *resc ... *rend.
  * Otherwise, *resc is set to aesc and the positions of the escape
  * sequence starting at aesc are returned.
- * Diagnostic messages are generated if and only if resc != NULL,
+ * Diagnostic messages are generated if and only if ln != 0,
  * that is, if and only if called by roff_expand().
  */
 enum mandoc_esc
@@ -72,11 +72,13 @@ roff_escape(const char *buf, const int ln, const int aesc,
        int              iendarg;       /* index right after the argument */
        int              iend;          /* index right after the sequence */
        int              sesc, snam, sarg, sendarg, send; /* for sub-escape */
+       int              escterm;       /* whether term is escaped */
        int              maxl;          /* expected length of the argument */
        int              argl;          /* actual length of the argument */
        int              c, i;          /* for \[char...] parsing */
        int              valid_A;       /* for \A parsing */
        enum mandoc_esc  rval;          /* return value */
+       enum mandoc_esc  stype;         /* for sub-escape */
        enum mandocerr   err;           /* diagnostic code */
        char             term;          /* byte terminating the argument */
 
@@ -264,13 +266,32 @@ roff_escape(const char *buf, const int ln, const int aesc,
 
        /* Decide how to end the argument. */
 
+       escterm = 0;
+       stype = ESCAPE_EXPAND;
        if ((term == '\b' || (term == '\0' && maxl == INT_MAX)) &&
-           buf[iarg] == buf[iesc] && roff_escape(buf, ln, iendarg,
-           &sesc, &snam, &sarg, &sendarg, &send) == ESCAPE_EXPAND)
-               goto out_sub;
+           buf[iarg] == buf[iesc]) {
+               stype = roff_escape(buf, ln, iendarg,
+                   &sesc, &snam, &sarg, &sendarg, &send);
+               if (stype == ESCAPE_EXPAND)
+                       goto out_sub;
+       }
 
        if (term == '\b') {
-               if (strchr("BDHLRSvxNhl", buf[inam]) != NULL &&
+               if (stype == ESCAPE_UNDEF)
+                       iarg++;
+               if (stype != ESCAPE_EXPAND && stype != ESCAPE_UNDEF) {
+                       if (strchr("BHLRSNhlvx", buf[inam]) != NULL &&
+                           strchr(" ,.0DLOXYZ^abdhlortuvx|~",
+                           buf[snam]) != NULL) {
+                               err = MANDOCERR_ESC_DELIM;
+                               iend = send;
+                               iarg = iendarg = sesc;
+                               goto out;
+                       }
+                       escterm = 1;
+                       iarg = send;
+                       term = buf[snam];
+               } else if (strchr("BDHLRSvxNhl", buf[inam]) != NULL &&
                    strchr(" %&()*+-./0123456789:<=>", buf[iarg]) != NULL) {
                        err = MANDOCERR_ESC_DELIM;
                        if (rval != ESCAPE_EXPAND)
@@ -280,7 +301,8 @@ roff_escape(const char *buf, const int ln, const int aesc,
                                goto out;
                        }
                }
-               term = buf[iarg++];
+               if (term == '\b')
+                       term = buf[iarg++];
        } else if (term == '\0' && maxl == INT_MAX) {
                if (buf[inam] == 'n' && (buf[iarg] == '+' || buf[iarg] == '-'))
                        iarg++;
@@ -311,34 +333,34 @@ roff_escape(const char *buf, const int ln, const int aesc,
        while (maxl > 0) {
                if (buf[iendarg] == '\0') {
                        err = MANDOCERR_ESC_INCOMPLETE;
-                       if (rval != ESCAPE_EXPAND)
+                       if (rval != ESCAPE_EXPAND &&
+                           rval != ESCAPE_OVERSTRIKE)
                                rval = ESCAPE_ERROR;
-                       /* Ignore an incomplete argument except for \w. */
-                       if (buf[inam] != 'w')
+                       /* Usually, ignore an incomplete argument. */
+                       if (strchr("Aow", buf[inam]) == NULL)
                                iendarg = iarg;
                        break;
                }
-               if (buf[iendarg] == term) {
-                       iend = iendarg + 1;
-                       break;
-               }
-               if (buf[inam] == 'N' &&
-                   isdigit((unsigned char)buf[iendarg]) == 0) {
+               if (escterm == 0 && buf[iendarg] == term) {
                        iend = iendarg + 1;
                        break;
                }
                if (buf[iendarg] == buf[iesc]) {
-                       switch (roff_escape(buf, ln, iendarg,
-                           &sesc, &snam, &sarg, &sendarg, &send)) {
-                       case ESCAPE_EXPAND:
+                       stype = roff_escape(buf, ln, iendarg,
+                           &sesc, &snam, &sarg, &sendarg, &send);
+                       if (stype == ESCAPE_EXPAND)
                                goto out_sub;
-                       case ESCAPE_UNDEF:
+                       iend = send;
+                       if (escterm == 1 &&
+                           (buf[snam] == term || buf[inam] == 'N'))
                                break;
-                       default:
+                       if (stype != ESCAPE_UNDEF)
                                valid_A = 0;
-                               break;
-                       }
-                       iendarg = iend = send;
+                       iendarg = send;
+               } else if (buf[inam] == 'N' &&
+                   isdigit((unsigned char)buf[iendarg]) == 0) {
+                       iend = iendarg + 1;
+                       break;
                } else {
                        if (buf[iendarg] == ' ' || buf[iendarg] == '\t')
                                valid_A = 0;
@@ -483,6 +505,8 @@ out_sub:
        rval = ESCAPE_EXPAND;
 
 out:
+       if (resc != NULL)
+               *resc = iesc;
        if (rnam != NULL)
                *rnam = inam;
        if (rarg != NULL)
@@ -491,7 +515,7 @@ out:
                *rendarg = iendarg;
        if (rend != NULL)
                *rend = iend;
-       if (resc == NULL)
+       if (ln == 0)
                return rval;
 
        /*
@@ -499,7 +523,6 @@ out:
         * from the parser, not when called from the formatters.
         */
 
-       *resc = iesc;
        switch (rval) {
        case ESCAPE_UNSUPP:
                err = MANDOCERR_ESC_UNSUPP;