Fix xmalloc_fgets_str so that it really does NOT strip terminator.

Add xmalloc_fgetline_str which does strip terminator,
and use it in dpkg instead of xmalloc_fgets_str.
netstat: use xmalloc_fgets_str - allows to eat strings with NULs
(this fixes bug with some weird /proc/net/unix input)

function                                             old     new   delta
xmalloc_fgets_internal                                 -     191    +191
xmalloc_fgetline_str                                   -      18     +18
do_info                                              116     120      +4
unix_do_one                                          451     447      -4
tcp_do_one                                           423     419      -4
send_tree                                            369     365      -4
xmalloc_fgets_str                                    178      15    -163
------------------------------------------------------------------------------
(add/remove: 2/0 grow/shrink: 1/4 up/down: 213/-175)           Total: 38 bytes
   text    data     bss     dec     hex filename
 778445     832    7344  786621   c00bd busybox_old
 778483     832    7344  786659   c00e3 busybox_unstripped
This commit is contained in:
Denis Vlasenko 2007-12-26 20:44:45 +00:00
parent d55268d0d4
commit abee3d0e0d
5 changed files with 48 additions and 40 deletions

View File

@ -602,7 +602,7 @@ static unsigned fill_package_struct(char *control_buffer)
&field_name, &field_value);
if (field_name == NULL) {
goto fill_package_struct_cleanup; /* Oh no, the dreaded goto statement! */
goto fill_package_struct_cleanup;
}
field_num = index_in_strings(field_names, field_name);
@ -745,7 +745,7 @@ static void index_status_file(const char *filename)
unsigned status_num;
status_file = xfopen(filename, "r");
while ((control_buffer = xmalloc_fgets_str(status_file, "\n\n")) != NULL) {
while ((control_buffer = xmalloc_fgetline_str(status_file, "\n\n")) != NULL) {
const unsigned package_num = fill_package_struct(control_buffer);
if (package_num != -1) {
status_node = xmalloc(sizeof(status_node_t));
@ -798,7 +798,7 @@ static void write_status_file(deb_file_t **deb_file)
int i = 0;
/* Update previously known packages */
while ((control_buffer = xmalloc_fgets_str(old_status_file, "\n\n")) != NULL) {
while ((control_buffer = xmalloc_fgetline_str(old_status_file, "\n\n")) != NULL) {
tmp_string = strstr(control_buffer, "Package:");
if (tmp_string == NULL) {
continue;

View File

@ -464,9 +464,12 @@ extern void xwrite(int fd, const void *buf, size_t count);
/* Reads and prints to stdout till eof, then closes FILE. Exits on error: */
extern void xprint_and_close_file(FILE *file);
extern char *xmalloc_fgets(FILE *file);
/* Read up to (and including) TERMINATING_STRING: */
/* Reads up to (and including) TERMINATING_STRING: */
extern char *xmalloc_fgets_str(FILE *file, const char *terminating_string);
/* Chops off TERMINATING_STRING: from the end: */
extern char *xmalloc_fgetline_str(FILE *file, const char *terminating_string);
/* Reads up to (and including) "\n" or NUL byte */
extern char *xmalloc_fgets(FILE *file);
/* Chops off '\n' from the end, unlike fgets: */
extern char *xmalloc_getline(FILE *file);
extern char *bb_get_chunk_from_file(FILE *file, int *end);

View File

@ -10,10 +10,7 @@
#include "libbb.h"
/* Read up to (and including) TERMINATING_STRING from FILE and return it.
* Return NULL on EOF. */
char *xmalloc_fgets_str(FILE *file, const char *terminating_string)
static char *xmalloc_fgets_internal(FILE *file, const char *terminating_string, int chop_off)
{
char *linebuf = NULL;
const int term_length = strlen(terminating_string);
@ -25,12 +22,12 @@ char *xmalloc_fgets_str(FILE *file, const char *terminating_string)
while (1) {
ch = fgetc(file);
if (ch == EOF) {
free(linebuf);
return NULL;
if (idx == 0)
return linebuf; /* NULL */
break;
}
/* grow the line buffer as necessary */
while (idx > linebufsz - 2) {
if (idx >= linebufsz) {
linebufsz += 200;
linebuf = xrealloc(linebuf, linebufsz);
}
@ -40,14 +37,30 @@ char *xmalloc_fgets_str(FILE *file, const char *terminating_string)
/* Check for terminating string */
end_string_offset = idx - term_length;
if (end_string_offset > 0
if (end_string_offset >= 0
&& memcmp(&linebuf[end_string_offset], terminating_string, term_length) == 0
) {
idx -= term_length;
if (chop_off)
idx -= term_length;
break;
}
}
/* Grow/shrink *first*, then store NUL */
linebuf = xrealloc(linebuf, idx + 1);
linebuf[idx] = '\0';
return linebuf;
}
/* Read up to TERMINATING_STRING from FILE and return it,
* including terminating string.
* Non-terminated string can be returned if EOF is reached.
* Return NULL if EOF is reached immediately. */
char *xmalloc_fgets_str(FILE *file, const char *terminating_string)
{
return xmalloc_fgets_internal(file, terminating_string, 0);
}
char *xmalloc_fgetline_str(FILE *file, const char *terminating_string)
{
return xmalloc_fgets_internal(file, terminating_string, 1);
}

View File

@ -12,11 +12,10 @@
#include "libbb.h"
/* This function reads an entire line from a text file, up to a newline
* or NUL byte, inclusive. It returns a malloc'ed char * which must be
* stored and free'ed by the caller. If end is NULL '\n' isn't considered
* or NUL byte, inclusive. It returns a malloc'ed char * which
* must be free'ed by the caller. If end is NULL '\n' isn't considered
* end of line. If end isn't NULL, length of the chunk read is stored in it.
* Return NULL if EOF/error */
char *bb_get_chunk_from_file(FILE *file, int *end)
{
int ch;

View File

@ -170,6 +170,11 @@ static void tcp_do_one(int lnr, char *line)
rem_addr, &rem_port, &state,
&txq, &rxq, &timer_run, &time_len, &retr, &uid, &timeout, &inode, more);
if (num < 10) {
bb_error_msg("warning, got bogus tcp line");
return;
}
if (strlen(local_addr) > 8) {
#if ENABLE_FEATURE_IPV6
build_ipv6_addr(local_addr, &localaddr);
@ -180,11 +185,6 @@ static void tcp_do_one(int lnr, char *line)
build_ipv4_addr(rem_addr, &remaddr);
}
if (num < 10) {
bb_error_msg("warning, got bogus tcp line");
return;
}
if ((rem_port && (flags & NETSTAT_CONNECTED))
|| (!rem_port && (flags & NETSTAT_LISTENING))
) {
@ -349,17 +349,16 @@ static void unix_do_one(int nr, char *line)
const char *ss_proto, *ss_state, *ss_type;
char ss_flags[32];
/* TODO: currently we stop at first NUL byte. Is it a problem? */
if (nr == 0)
return; /* skip header */
{
char *last = last_char_is(line, '\n');
if (last)
*last = '\0';
}
*strchrnul(line, '\n') = '\0';
/* 2.6.15 may report lines like "... @/tmp/fam-user-^@^@^@^@^@^@^@..."
* (those ^@ are NUL bytes). fgets sees them as tons of empty lines. */
* Other users report long lines filled by NUL bytes.
* (those ^@ are NUL bytes too). We see them as empty lines. */
if (!line[0])
return;
@ -474,20 +473,14 @@ static void do_info(const char *file, const char *name, void (*proc)(int, char *
return;
}
lnr = 0;
do {
buffer = xmalloc_fgets(procinfo);
if (buffer) {
(proc)(lnr++, buffer);
free(buffer);
}
} while (buffer);
/* Why? because xmalloc_fgets_str doesn't stop on NULs */
while ((buffer = xmalloc_fgets_str(procinfo, "\n")) != NULL) {
(proc)(lnr++, buffer);
free(buffer);
}
fclose(procinfo);
}
/*
* Our main function.
*/
int netstat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int netstat_main(int argc, char **argv)
{