Hello tech@,
Here's a complete restructuring of the column(1) utility. It's aim is to
ease the implementation of UTF-8 support, which will come in a separate
patch, but also fixes a few bugs while here:
- Fix the width-calculation of a tab-character
- Correct treatment of files without trailing newlines.
- Repair "-xc 7"
- Overflow protection for the number of rows and columns
This patch already had loads of feedback from, and is OK by schwarze@.
Without any objections I'd like to commit this by the end of the
hackathon. Extra OKs welcome.
martijn@
Index: column.c
===================================================================
RCS file: /cvs/src/usr.bin/column/column.c,v
retrieving revision 1.23
diff -u -p -r1.23 column.c
--- column.c 17 Mar 2016 05:27:10 -0000 1.23
+++ column.c 31 Aug 2016 19:52:47 -0000
@@ -48,14 +48,18 @@ void input(FILE *);
void maketbl(void);
void print(void);
void r_columnate(void);
-void usage(void);
+__dead void usage(void);
-int termwidth; /* default terminal width */
+struct field {
+ char *content;
+ int width;
+};
+int termwidth; /* default terminal width */
int entries; /* number of records */
int eval; /* exit value */
-int maxlength; /* longest record */
-char **list; /* array of pointers to records */
+int *maxwidths; /* longest record per column */
+struct field **table; /* one array of pointers per line */
char *separator = "\t "; /* field separator for table option */
int
@@ -80,7 +84,7 @@ main(int argc, char *argv[])
err(1, "pledge");
tflag = xflag = 0;
- while ((ch = getopt(argc, argv, "c:s:tx")) != -1)
+ while ((ch = getopt(argc, argv, "c:s:tx")) != -1) {
switch(ch) {
case 'c':
termwidth = strtonum(optarg, 1, INT_MAX, &errstr);
@@ -96,14 +100,16 @@ main(int argc, char *argv[])
case 'x':
xflag = 1;
break;
- case '?':
default:
usage();
}
- argc -= optind;
+ }
+
+ if (!tflag)
+ separator = "";
argv += optind;
- if (!*argv) {
+ if (*argv == NULL) {
input(stdin);
} else {
for (; *argv; ++argv) {
@@ -121,73 +127,63 @@ main(int argc, char *argv[])
err(1, "pledge");
if (!entries)
- exit(eval);
+ return eval;
if (tflag)
maketbl();
- else if (maxlength >= termwidth)
+ else if (*maxwidths >= termwidth)
print();
else if (xflag)
c_columnate();
else
r_columnate();
- exit(eval);
+ return eval;
}
-#define TAB 8
+#define INCR_NEXTTAB(x) (x = (x + 8) & ~7)
void
c_columnate(void)
{
- int chcnt, col, cnt, endcol, numcols;
- char **lp;
+ int col, numcols;
+ struct field **row;
- maxlength = (maxlength + TAB) & ~(TAB - 1);
- numcols = termwidth / maxlength;
- endcol = maxlength;
- for (chcnt = col = 0, lp = list;; ++lp) {
- chcnt += printf("%s", *lp);
+ INCR_NEXTTAB(*maxwidths);
+ if ((numcols = termwidth / *maxwidths) == 0)
+ numcols = 1;
+ for (col = 0, row = table;; ++row) {
+ fputs((*row)->content, stdout);
if (!--entries)
break;
if (++col == numcols) {
- chcnt = col = 0;
- endcol = maxlength;
+ col = 0;
putchar('\n');
} else {
- while ((cnt = ((chcnt + TAB) & ~(TAB - 1))) <= endcol) {
- (void)putchar('\t');
- chcnt = cnt;
- }
- endcol += maxlength;
+ while (INCR_NEXTTAB((*row)->width) <= *maxwidths)
+ putchar('\t');
}
}
- if (chcnt)
- putchar('\n');
+ putchar('\n');
}
void
r_columnate(void)
{
- int base, chcnt, cnt, col, endcol, numcols, numrows, row;
+ int base, col, numcols, numrows, row;
- maxlength = (maxlength + TAB) & ~(TAB - 1);
- numcols = termwidth / maxlength;
- if (numcols == 0)
+ INCR_NEXTTAB(*maxwidths);
+ if ((numcols = termwidth / *maxwidths) == 0)
numcols = 1;
numrows = entries / numcols;
if (entries % numcols)
++numrows;
- for (row = 0; row < numrows; ++row) {
- endcol = maxlength;
- for (base = row, chcnt = col = 0; col < numcols; ++col) {
- chcnt += printf("%s", list[base]);
- if ((base += numrows) >= entries)
+ for (base = row = 0; row < numrows; base = ++row) {
+ for (col = 0; col < numcols; ++col, base += numrows) {
+ fputs(table[base]->content, stdout);
+ if (base + numrows >= entries)
break;
- while ((cnt = ((chcnt + TAB) & ~(TAB - 1))) <= endcol) {
- (void)putchar('\t');
- chcnt = cnt;
- }
- endcol += maxlength;
+ while (INCR_NEXTTAB(table[base]->width) <= *maxwidths)
+ putchar('\t');
}
putchar('\n');
}
@@ -196,126 +192,144 @@ r_columnate(void)
void
print(void)
{
- int cnt;
- char **lp;
+ int row;
- for (cnt = entries, lp = list; cnt--; ++lp)
- (void)printf("%s\n", *lp);
+ for (row = 0; row < entries; row++)
+ puts(table[row]->content);
}
-typedef struct _tbl {
- char **list;
- int cols, *len;
-} TBL;
-#define DEFCOLS 25
void
maketbl(void)
{
- TBL *t;
- int coloff, cnt;
- char *p, **lp;
- int *lens, maxcols = DEFCOLS;
- TBL *tbl;
- char **cols;
-
- t = tbl = ecalloc(entries, sizeof(TBL));
- cols = ereallocarray(NULL, maxcols, sizeof(char *));
- lens = ecalloc(maxcols, sizeof(int));
- for (cnt = 0, lp = list; cnt < entries; ++cnt, ++lp, ++t) {
- for (coloff = 0, p = *lp; (cols[coloff] = strtok(p, separator));
- p = NULL)
- if (++coloff == maxcols) {
- maxcols += DEFCOLS;
- cols = ereallocarray(cols, maxcols,
- sizeof(char *));
- lens = ereallocarray(lens, maxcols,
- sizeof(int));
- memset(lens + coloff, 0, DEFCOLS * sizeof(int));
- }
- if (coloff == 0)
- continue;
- t->list = ecalloc(coloff, sizeof(char *));
- t->len = ecalloc(coloff, sizeof(int));
- for (t->cols = coloff; --coloff >= 0;) {
- t->list[coloff] = cols[coloff];
- t->len[coloff] = strlen(cols[coloff]);
- if (t->len[coloff] > lens[coloff])
- lens[coloff] = t->len[coloff];
- }
- }
- for (cnt = 0, t = tbl; cnt < entries; ++cnt, ++t) {
- if (t->cols > 0) {
- for (coloff = 0; coloff < t->cols - 1; ++coloff)
- (void)printf("%s%*s", t->list[coloff],
- lens[coloff] - t->len[coloff] + 2, " ");
- (void)printf("%s\n", t->list[coloff]);
- }
+ struct field **row;
+ int col;
+
+ for (row = table; entries--; ++row) {
+ for (col = 0; (*row)[col + 1].content != NULL; ++col)
+ printf("%s%*s ", (*row)[col].content,
+ maxwidths[col] - (*row)[col].width, "");
+ puts((*row)[col].content);
}
- free(tbl);
- free(lens);
- free(cols);
}
#define DEFNUM 1000
-#define MAXLINELEN (LINE_MAX + 1)
+#define DEFCOLS 25
void
input(FILE *fp)
{
- static size_t maxentry = DEFNUM;
- int len;
- char *p, buf[MAXLINELEN];
-
- if (!list)
- list = ecalloc(maxentry, sizeof(char *));
- while (fgets(buf, MAXLINELEN, fp)) {
- for (p = buf; isspace((unsigned char)*p); ++p);
- if (!*p)
- continue;
- if (!(p = strchr(p, '\n'))) {
- warnx("line too long");
- eval = 1;
- continue;
+ static int maxentry = 0;
+ static int maxcols = 0;
+ static struct field *cols = NULL;
+ int col, width;
+ size_t blen;
+ ssize_t llen;
+ char *p, *s, *buf = NULL;
+
+ while ((llen = getline(&buf, &blen, fp)) > -1) {
+ if (buf[llen - 1] == '\n')
+ buf[llen - 1] = '\0';
+
+ p = buf;
+ for (col = 0;; col++) {
+
+ /* Skip lines containing nothing but whitespace. */
+
+ for (s = p; s != '\0'; s++)
+ if (!isspace((unsigned char)*s))
+ break;
+ if (*s == '\0')
+ break;
+
+ /* Skip leading, multiple, and trailing separators. */
+
+ while (*p != '\0' && strchr(separator, *p) != NULL)
+ p++;
+ if (*p == '\0')
+ break;
+
+ /*
+ * Found a non-empty field.
+ * Remember the start and measure the width.
+ */
+
+ s = p;
+ width = 0;
+ while (*p != '\0' && strchr(separator, *p) == NULL) {
+ if (*p++ == '\t')
+ INCR_NEXTTAB(width);
+ else
+ width++;
+ }
+
+ if (col + 1 >= maxcols) {
+ if (maxcols > INT_MAX - DEFCOLS)
+ err(1, "too many columns");
+ maxcols += DEFCOLS;
+ cols = ereallocarray(cols, maxcols,
+ sizeof(*cols));
+ maxwidths = ereallocarray(maxwidths, maxcols,
+ sizeof(*maxwidths));
+ memset(maxwidths + col, 0,
+ DEFCOLS * sizeof(*maxwidths));
+ }
+
+ /*
+ * Remember the width of the field,
+ * NUL-terminate and remeber the content,
+ * and advance beyond the separator, if any.
+ */
+
+ cols[col].width = width;
+ if (maxwidths[col] < width)
+ maxwidths[col] = width;
+ if (*p != '\0')
+ *p++ = '\0';
+ if ((cols[col].content = strdup(s)) == NULL)
+ err(1, NULL);
}
- *p = '\0';
- len = p - buf;
- if (maxlength < len)
- maxlength = len;
+ if (col == 0)
+ continue;
+
+ /* Found a non-empty line; remember it. */
+
if (entries == maxentry) {
+ if (maxentry > INT_MAX - DEFNUM)
+ errx(1, "too many input lines");
maxentry += DEFNUM;
- list = ereallocarray(list, maxentry, sizeof(char *));
- memset(list + entries, 0, DEFNUM * sizeof(char *));
+ table = ereallocarray(table, maxentry, sizeof(*table));
}
- if (!(list[entries++] = strdup(buf)))
- err(1, NULL);
+ table[entries] = ereallocarray(NULL, col + 1,
+ sizeof(*(table[entries])));
+ table[entries][col].content = NULL;
+ while (col--)
+ table[entries][col] = cols[col];
+ entries++;
}
}
void *
-ereallocarray(void *oldp, size_t sz1, size_t sz2)
+ereallocarray(void *ptr, size_t nmemb, size_t size)
{
- void *p;
-
- if (!(p = reallocarray(oldp, sz1, sz2)))
+ if ((ptr = reallocarray(ptr, nmemb, size)) == NULL)
err(1, NULL);
- return (p);
+ return ptr;
}
void *
-ecalloc(size_t sz1, size_t sz2)
+ecalloc(size_t nmemb, size_t size)
{
- void *p;
+ void *ptr;
- if (!(p = calloc(sz1, sz2)))
+ if ((ptr = calloc(nmemb, size)) == NULL)
err(1, NULL);
- return (p);
+ return ptr;
}
-void
+__dead void
usage(void)
{
-
(void)fprintf(stderr,
"usage: column [-tx] [-c columns] [-s sep] [file ...]\n");
exit(1);
