diff options
Diffstat (limited to 'json_print.c')
| -rw-r--r-- | json_print.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/json_print.c b/json_print.c new file mode 100644 index 0000000..4f62767 --- /dev/null +++ b/json_print.c @@ -0,0 +1,228 @@ +/* + * json_print.c "print regular or json output, based on json_writer". + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * Authors: Julien Fortin, <julien@cumulusnetworks.com> + */ + +#include <stdarg.h> +#include <stdio.h> +#include <unistd.h> +#include <stdlib.h> + +#include "json_print.h" + +#define SPRINT_BSIZE 64 +#define SPRINT_BUF(x) char x[SPRINT_BSIZE] + +static json_writer_t *_jw; + +#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) +{ + if (json) { + _jw = jsonw_new(stdout); + if (!_jw) { + perror("json object"); + exit(1); + } + jsonw_pretty(_jw, true); + jsonw_start_array(_jw); + } +} + +void delete_json_obj(void) +{ + if (_jw) { + jsonw_end_array(_jw); + jsonw_destroy(&_jw); + } +} + +bool is_json_context(void) +{ + return _jw != NULL; +} + +json_writer_t *get_json_writer(void) +{ + return _jw; +} + +void open_json_object(const char *str) +{ + if (_IS_JSON_CONTEXT(PRINT_JSON)) { + if (str) + jsonw_name(_jw, str); + jsonw_start_object(_jw); + } +} + +void close_json_object(void) +{ + if (_IS_JSON_CONTEXT(PRINT_JSON)) + jsonw_end_object(_jw); +} + +/* + * Start json array or string array using + * the provided string as json key (if not null) + * or array delimiter in non-json context. + */ +void open_json_array(const char *key, const char *str) +{ + if (is_json_context()) { + if (key) + jsonw_name(_jw, key); + jsonw_start_array(_jw); + } else { + printf("%s", str); + } +} + +/* + * End json array or string array + */ +void close_json_array(const char *delim) +{ + if (is_json_context()) + jsonw_end_array(_jw); + else + printf("%s", delim); +} + +/* + * pre-processor directive to generate similar + * functions handling different types + */ +#define _PRINT_FUNC(type_name, type) \ + __attribute__((format(printf, 3, 0))) \ + void print_##type_name(enum output_type t, \ + const char *key, \ + const char *fmt, \ + type value) \ + { \ + if (_IS_JSON_CONTEXT(t)) { \ + if (!key) \ + jsonw_##type_name(_jw, value); \ + else \ + jsonw_##type_name##_field(_jw, key, value); \ + } else if (_IS_FP_CONTEXT(t)) { \ + fprintf(stdout, fmt, value); \ + } \ + } +_PRINT_FUNC(int, int); +_PRINT_FUNC(s64, int64_t); +_PRINT_FUNC(hhu, unsigned char); +_PRINT_FUNC(hu, unsigned short); +_PRINT_FUNC(uint, unsigned int); +_PRINT_FUNC(u64, uint64_t); +_PRINT_FUNC(luint, unsigned long); +_PRINT_FUNC(lluint, unsigned long long); +_PRINT_FUNC(float, double); +#undef _PRINT_FUNC + +void print_string(enum output_type type, + const char *key, + const char *fmt, + const char *value) +{ + if (_IS_JSON_CONTEXT(type)) { + if (key && !value) + jsonw_name(_jw, key); + else if (!key && value) + jsonw_string(_jw, value); + else + jsonw_string_field(_jw, key, value); + } else if (_IS_FP_CONTEXT(type)) { + fprintf(stdout, fmt, value); + } +} + +/* + * value's type is bool. When using this function in FP context you can't pass + * a value to it, you will need to use "is_json_context()" to have different + * branch for json and regular output. grep -r "print_bool" for example + */ +void print_bool(enum output_type type, + const char *key, + const char *fmt, + bool value) +{ + if (_IS_JSON_CONTEXT(type)) { + if (key) + jsonw_bool_field(_jw, key, value); + else + jsonw_bool(_jw, value); + } else if (_IS_FP_CONTEXT(type)) { + fprintf(stdout, fmt, value ? "true" : "false"); + } +} + +/* + * In JSON context uses hardcode %#x format: 42 -> 0x2a + */ +void print_0xhex(enum output_type type, + const char *key, + const char *fmt, + unsigned long long hex) +{ + if (_IS_JSON_CONTEXT(type)) { + SPRINT_BUF(b1); + + snprintf(b1, sizeof(b1), "%#llx", hex); + print_string(PRINT_JSON, key, NULL, b1); + } else if (_IS_FP_CONTEXT(type)) { + fprintf(stdout, fmt, hex); + } +} + +void print_hex(enum output_type type, + const char *key, + const char *fmt, + unsigned int hex) +{ + if (_IS_JSON_CONTEXT(type)) { + SPRINT_BUF(b1); + + snprintf(b1, sizeof(b1), "%x", hex); + if (key) + jsonw_string_field(_jw, key, b1); + else + jsonw_string(_jw, b1); + } else if (_IS_FP_CONTEXT(type)) { + fprintf(stdout, fmt, hex); + } +} + +/* + * In JSON context we don't use the argument "value" we simply call jsonw_null + * whereas FP context can use "value" to output anything + */ +void print_null(enum output_type type, + const char *key, + const char *fmt, + const char *value) +{ + if (_IS_JSON_CONTEXT(type)) { + if (key) + jsonw_null_field(_jw, key); + else + jsonw_null(_jw); + } else if (_IS_FP_CONTEXT(type)) { + fprintf(stdout, fmt, value); + } +} + +/* Print line separator (if not in JSON mode) */ +void print_nl(void) +{ + if (!_jw) + printf("%s", "\n"); +} |