Line 0 is a special line added to allow operations with empty buffers, and we have to ensure that it is not going to match any regular expression. The code was written in a way that this case was handle implicitily, but this solution was working only for the first file loaded in ed, while the second file loaded in ed got a line with a dirty seek field. This solution check explicitily against invalid lines passed to makeline(), which allows to simplify the common case. --- ed.c | 31 +++++++++++++++++-------------- 1 file changed, 17 insertions(+), 14 deletions(-)
diff --git a/ed.c b/ed.c index 686d2aa..09eadd9 100644 --- a/ed.c +++ b/ed.c @@ -169,20 +169,20 @@ makeline(char *s, int *off) } lp = zero + lastidx; - while ((c = *s) && *s != '\n') - ++s; - if (c == '\n') - ++s; - len = s - begin; + if (!s) { + lp->seek = -1; + len = 0; + } else { + while ((c = *s) != '\n') + ++s; + len = s - begin; + if ((lp->seek = lseek(scratch, 0, SEEK_END)) < 0 || + write(scratch, begin, len) < 0) { + error("input/output error"); + } + } if (off) *off = len; - - if (len > 0) - if ((lp->seek = lseek(scratch, 0, SEEK_END)) < 0 || - write(scratch, begin, len) < 0) { - error("input/output error"); - } - ++lastidx; return lp - zero; } @@ -210,8 +210,11 @@ gettxt(int line) char *p; lp = zero + getindex(line); - off = lp->seek; sizetxt = 0; + off = lp->seek; + + if (off == (off_t) -1) + return text = addchar('\0', text, &memtxt, &sizetxt); repeat: if (!csize || off < lasto || off - lasto >= csize) { @@ -341,7 +344,7 @@ setscratch() error("scratch filename too long"); if ((scratch = mkstemp(tmpname)) < 0) error("failed to create scratch file"); - if ((k = makeline("", NULL))) + if ((k = makeline(NULL, NULL))) error("input/output error in scratch file"); relink(k, k, k, k); clearundo(); -- 2.1.4