bcachefs: Fix pr_tab_rjust()

pr_tab_rjust() was broken and leaving a null somewhere in the output
string - this patch fixes it and simplifies it a bit.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

diff --git a/fs/bcachefs/util.c b/fs/bcachefs/util.c
index 7a896ddc9a22d7c555fe5c1f0f0343336e9d7076..f290c069c6830a3c3f2c0d486d9907cbc6f72b89 100644 (file)
--- a/fs/bcachefs/util.c
+++ b/fs/bcachefs/util.c
@@ -101,8 +101,14 @@ STRTO_H(strtou64, u64)
 
 static int bch2_printbuf_realloc(struct printbuf *out, unsigned extra)
 {
-       unsigned new_size = roundup_pow_of_two(out->size + extra);
-       char *buf = krealloc(out->buf, new_size, !out->atomic ? GFP_KERNEL : GFP_ATOMIC);
+       unsigned new_size;
+       char *buf;
+
+       if (out->pos + extra + 1 < out->size)
+               return 0;
+
+       new_size = roundup_pow_of_two(out->size + extra);
+       buf = krealloc(out->buf, new_size, !out->atomic ? GFP_KERNEL : GFP_ATOMIC);
 
        if (!buf) {
                out->allocation_failure = true;
@@ -131,6 +137,33 @@ void bch2_pr_buf(struct printbuf *out, const char *fmt, ...)
        out->pos += len;
 }
 
+void bch2_pr_tab_rjust(struct printbuf *buf)
+{
+       BUG_ON(buf->tabstop > ARRAY_SIZE(buf->tabstops));
+
+       if (printbuf_linelen(buf) < buf->tabstops[buf->tabstop]) {
+               unsigned move = buf->pos - buf->last_field;
+               unsigned shift = buf->tabstops[buf->tabstop] -
+                       printbuf_linelen(buf);
+
+               bch2_printbuf_realloc(buf, shift);
+
+               if (buf->last_field + shift + 1 < buf->size) {
+                       move = min(move, buf->size - 1 - buf->last_field - shift);
+
+                       memmove(buf->buf + buf->last_field + shift,
+                               buf->buf + buf->last_field,
+                               move);
+                       memset(buf->buf + buf->last_field, ' ', shift);
+                       buf->pos += shift;
+                       buf->buf[buf->pos] = 0;
+               }
+       }
+
+       buf->last_field = buf->pos;
+       buf->tabstop++;
+}
+
 void bch2_hprint(struct printbuf *buf, s64 v)
 {
        int u, t = 0;

diff --git a/fs/bcachefs/util.h b/fs/bcachefs/util.h
index 7667944f9ae49acfe7e65a5774ff5c964f4c633f..ba0c4d29c0388928fda79a07ca32fead2a284020 100644 (file)
--- a/fs/bcachefs/util.h
+++ b/fs/bcachefs/util.h
@@ -334,27 +334,11 @@ static inline void pr_tab(struct printbuf *buf)
        buf->tabstop++;
 }
 
+void bch2_pr_tab_rjust(struct printbuf *);
+
 static inline void pr_tab_rjust(struct printbuf *buf)
 {
-       ssize_t shift = min_t(ssize_t, buf->tabstops[buf->tabstop] -
-                             printbuf_linelen(buf),
-                             printbuf_remaining(buf));
-       ssize_t move = min_t(ssize_t, buf->pos - buf->last_field,
-                            printbuf_remaining(buf) - shift);
-
-       BUG_ON(buf->tabstop > ARRAY_SIZE(buf->tabstops));
-
-       if (shift > 0) {
-               memmove(buf->buf + buf->last_field + shift,
-                       buf->buf + buf->last_field,
-                       move);
-               memset(buf->buf + buf->last_field, ' ', shift);
-               buf->pos += shift;
-               buf->buf[buf->pos] = 0;
-       }
-
-       buf->last_field = buf->pos;
-       buf->tabstop++;
+       bch2_pr_tab_rjust(buf);
 }
 
 void bch2_pr_units(struct printbuf *, s64, s64);