From: Julien Fortin <jul...@cumulusnetworks.com> As Stephen Hemminger mentioned on the last submission the new_json_obj function is always called with fp == stdout, so right now, there's no need of this extra argument.
The background for the rework is the following: The ip monitor didn't call `new_json_obj` (even for in non json context), so the static FILE* _fp variable wasn't initialized, thus raising a SIGSEGV in ipaddress.c. This patch should fix this issue for good, new paths won't have to call `new_json_obj`. How to reproduce: $ ip -t mon label link (gdb) bt .#0 _IO_vfprintf_internal (s=s@entry=0x0, format=format@entry=0x45460d “%d: “, ap=ap@entry=0x7fffffff7f18) at vfprintf.c:1278 .#1 0x0000000000451310 in color_fprintf (fp=0x0, attr=<optimized out>, fmt=0x45460d “%d: “) at color.c:108 .#2 0x000000000044a856 in print_color_int (t=t@entry=PRINT_ANY, color=color@entry=4294967295, key=key@entry=0x4545fc “ifindex”, fmt=fmt@entry=0x45460d “%d: “, value=<optimized out>) at ip_print.c:132 .#3 0x000000000040ccd2 in print_int (value=<optimized out>, fmt=0x45460d “%d: “, key=0x4545fc “ifindex”, t=PRINT_ANY) at ip_common.h:189 .#4 print_linkinfo (who=<optimized out>, n=0x7fffffffa380, arg=0x7ffff77a82a0 <_IO_2_1_stdout_>) at ipaddress.c:1107 .#5 0x0000000000422e13 in accept_msg (who=0x7fffffff8320, ctrl=0x7fffffff8310, n=0x7fffffffa380, arg=0x7ffff77a82a0 <_IO_2_1_stdout_>) at ipmonitor.c:89 .#6 0x000000000044c58f in rtnl_listen (rtnl=0x672160 <rth>, handler=handler@entry=0x422c70 <accept_msg>, jarg=0x7ffff77a82a0 <_IO_2_1_stdout_>) at libnetlink.c:761 .#7 0x00000000004233db in do_ipmonitor (argc=<optimized out>, argv=0x7fffffffe5a0) at ipmonitor.c:310 .#8 0x0000000000408f74 in do_cmd (argv0=0x7fffffffe7f5 “mon”, argc=3, argv=0x7fffffffe588) at ip.c:116 .#9 0x0000000000408a94 in main (argc=4, argv=0x7fffffffe580) at ip.c:311 Fixes: 6377572f ("ip: ip_print: add new API to print JSON or regular format output") Reported-by: David Ahern <d...@cumulusnetworks.com> Signed-off-by: Julien Fortin <jul...@cumulusnetworks.com> --- include/json_print.h | 4 +--- ip/ipaddress.c | 4 ++-- lib/json_print.c | 31 ++++++++++--------------------- 3 files changed, 13 insertions(+), 26 deletions(-) diff --git a/include/json_print.h b/include/json_print.h index 44cf5ac5..b6ce1f9f 100644 --- a/include/json_print.h +++ b/include/json_print.h @@ -29,13 +29,11 @@ enum output_type { PRINT_ANY = 4, }; -void new_json_obj(int json, FILE *fp); +void new_json_obj(int json); void delete_json_obj(void); bool is_json_context(void); -void set_current_fp(FILE *fp); - void fflush_fp(void); void open_json_object(const char *str); diff --git a/ip/ipaddress.c b/ip/ipaddress.c index b8bc387a..9e9a7e0a 100644 --- a/ip/ipaddress.c +++ b/ip/ipaddress.c @@ -1815,7 +1815,7 @@ static int ipaddr_showdump(void) if (ipadd_dump_check_magic()) exit(-1); - new_json_obj(json, stdout); + new_json_obj(json); open_json_object(NULL); open_json_array(PRINT_JSON, "addr_info"); @@ -2176,7 +2176,7 @@ static int ipaddr_list_flush_or_save(int argc, char **argv, int action) * Initialize a json_writer and open an array object * if -json was specified. */ - new_json_obj(json, stdout); + new_json_obj(json); /* * If only filter_dev present and none of the other diff --git a/lib/json_print.c b/lib/json_print.c index 93b4119d..aa527af6 100644 --- a/lib/json_print.c +++ b/lib/json_print.c @@ -16,15 +16,14 @@ #include "json_print.h" static json_writer_t *_jw; -static FILE *_fp; #define _IS_JSON_CONTEXT(type) ((type & PRINT_JSON || type & PRINT_ANY) && _jw) #define _IS_FP_CONTEXT(type) (!_jw && (type & PRINT_FP || type & PRINT_ANY)) -void new_json_obj(int json, FILE *fp) +void new_json_obj(int json) { if (json) { - _jw = jsonw_new(fp); + _jw = jsonw_new(stdout); if (!_jw) { perror("json object"); exit(1); @@ -32,7 +31,6 @@ void new_json_obj(int json, FILE *fp) jsonw_pretty(_jw, true); jsonw_start_array(_jw); } - set_current_fp(fp); } void delete_json_obj(void) @@ -48,15 +46,6 @@ bool is_json_context(void) return _jw != NULL; } -void set_current_fp(FILE *fp) -{ - if (!fp) { - fprintf(stderr, "Error: invalid file pointer.\n"); - exit(1); - } - _fp = fp; -} - json_writer_t *get_json_writer(void) { return _jw; @@ -89,7 +78,7 @@ void open_json_array(enum output_type type, const char *str) jsonw_name(_jw, str); jsonw_start_array(_jw); } else if (_IS_FP_CONTEXT(type)) { - fprintf(_fp, "%s", str); + printf("%s", str); } } @@ -103,7 +92,7 @@ void close_json_array(enum output_type type, const char *str) jsonw_end_array(_jw); jsonw_pretty(_jw, true); } else if (_IS_FP_CONTEXT(type)) { - fprintf(_fp, "%s", str); + printf("%s", str); } } @@ -124,7 +113,7 @@ void close_json_array(enum output_type type, const char *str) else \ jsonw_##type_name##_field(_jw, key, value); \ } else if (_IS_FP_CONTEXT(t)) { \ - color_fprintf(_fp, color, fmt, value); \ + color_fprintf(stdout, color, fmt, value); \ } \ } _PRINT_FUNC(int, int); @@ -147,7 +136,7 @@ void print_color_string(enum output_type type, else jsonw_string_field(_jw, key, value); } else if (_IS_FP_CONTEXT(type)) { - color_fprintf(_fp, color, fmt, value); + color_fprintf(stdout, color, fmt, value); } } @@ -168,7 +157,7 @@ void print_color_bool(enum output_type type, else jsonw_bool(_jw, value); } else if (_IS_FP_CONTEXT(type)) { - color_fprintf(_fp, color, fmt, value ? "true" : "false"); + color_fprintf(stdout, color, fmt, value ? "true" : "false"); } } @@ -187,7 +176,7 @@ void print_color_0xhex(enum output_type type, snprintf(b1, sizeof(b1), "%#x", hex); print_string(PRINT_JSON, key, NULL, b1); } else if (_IS_FP_CONTEXT(type)) { - color_fprintf(_fp, color, fmt, hex); + color_fprintf(stdout, color, fmt, hex); } } @@ -206,7 +195,7 @@ void print_color_hex(enum output_type type, else jsonw_string(_jw, b1); } else if (_IS_FP_CONTEXT(type)) { - color_fprintf(_fp, color, fmt, hex); + color_fprintf(stdout, color, fmt, hex); } } @@ -226,6 +215,6 @@ void print_color_null(enum output_type type, else jsonw_null(_jw); } else if (_IS_FP_CONTEXT(type)) { - color_fprintf(_fp, color, fmt, value); + color_fprintf(stdout, color, fmt, value); } } -- 2.14.1