library: help ensure 'escape_str' isn't executed twice

Now that the ps program is using 'escape_str' for most
of the library's returned strings, this patch tries to
lessen the prospects of executing that function twice.

Our newlib branch has achieved such a goal through the
elimination of nearly all escape.c code. However, here
we avoid API change by trading some 'escape_str' calls
(with wide character overhead) for a slightly extended
'escaped_copy' call (which incurs no multibyte costs).

Note: until we migrate to the newlib version, there is
a remaining call to 'escape_str' which we can't avoid.
Such code involves the 'escape_command' function call.

[ As we prepare for this new (final?) release, there ]
[ were already internal library changes that require ]
[ a new 'revision'. This patch won't impact the API! ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit is contained in:
Jim Warner 2020-12-26 00:00:00 -06:00 committed by Craig Small
parent c76144ead1
commit eea5626bb1
2 changed files with 11 additions and 5 deletions

View File

@ -222,10 +222,10 @@ int escape_command(char *restrict const outbuf, const proc_t *restrict const pp,
///////////////////////////////////////////////// /////////////////////////////////////////////////
// copy an already 'escaped' string, // copy a string, but 'escape' any control characters
// using the traditional escape.h calling conventions // using the traditional escape.h calling conventions
int escaped_copy(char *restrict dst, const char *restrict src, int bufsize, int *maxroom){ int escaped_copy(char *restrict dst, const char *restrict src, int bufsize, int *maxroom){
int n; int i, n;
SECURE_ESCAPE_ARGS(dst, bufsize, *maxroom); SECURE_ESCAPE_ARGS(dst, bufsize, *maxroom);
if (bufsize > *maxroom+1) bufsize = *maxroom+1; if (bufsize > *maxroom+1) bufsize = *maxroom+1;
@ -236,6 +236,12 @@ int escaped_copy(char *restrict dst, const char *restrict src, int bufsize, int
return 0; return 0;
} }
if (n >= bufsize) n = bufsize-1; if (n >= bufsize) n = bufsize-1;
// control chars, especially tabs, create alignment problems for ps & top ...
for (i = 0; i < n; i++)
if ((unsigned char)dst[i] < 0x20 || dst[i] == 0x7f)
dst[i] = '?';
*maxroom -= n; *maxroom -= n;
return n; return n;
} }

View File

@ -844,7 +844,7 @@ static void fill_cgroup_cvt (const char* directory, proc_t *restrict p) {
len = snprintf(dst, vMAX, "%s", (dst > dst_buffer) ? "," : ""); len = snprintf(dst, vMAX, "%s", (dst > dst_buffer) ? "," : "");
if (len < 0 || len >= vMAX) break; if (len < 0 || len >= vMAX) break;
dst += len; dst += len;
dst += escape_str(dst, grp, vMAX, &whackable_int); dst += escaped_copy(dst, grp, vMAX, &whackable_int);
} }
p->cgroup = vectorize_this_str(dst_buffer[0] ? dst_buffer : "-"); p->cgroup = vectorize_this_str(dst_buffer[0] ? dst_buffer : "-");
@ -862,7 +862,7 @@ static void fill_cmdline_cvt (const char* directory, proc_t *restrict p) {
int whackable_int = MAX_BUFSZ; int whackable_int = MAX_BUFSZ;
if (read_unvectored(src_buffer, MAX_BUFSZ, directory, "cmdline", ' ')) if (read_unvectored(src_buffer, MAX_BUFSZ, directory, "cmdline", ' '))
escape_str(dst_buffer, src_buffer, MAX_BUFSZ, &whackable_int); escaped_copy(dst_buffer, src_buffer, MAX_BUFSZ, &whackable_int);
else else
escape_command(dst_buffer, p, MAX_BUFSZ, &whackable_int, uFLG); escape_command(dst_buffer, p, MAX_BUFSZ, &whackable_int, uFLG);
p->cmdline = vectorize_this_str(dst_buffer); p->cmdline = vectorize_this_str(dst_buffer);
@ -876,7 +876,7 @@ static void fill_environ_cvt (const char* directory, proc_t *restrict p) {
dst_buffer[0] = '\0'; dst_buffer[0] = '\0';
if (read_unvectored(src_buffer, MAX_BUFSZ, directory, "environ", ' ')) if (read_unvectored(src_buffer, MAX_BUFSZ, directory, "environ", ' '))
escape_str(dst_buffer, src_buffer, MAX_BUFSZ, &whackable_int); escaped_copy(dst_buffer, src_buffer, MAX_BUFSZ, &whackable_int);
p->environ = vectorize_this_str(dst_buffer[0] ? dst_buffer : "-"); p->environ = vectorize_this_str(dst_buffer[0] ? dst_buffer : "-");
} }