diff options
Diffstat (limited to 'src/json.c')
| -rw-r--r-- | src/json.c | 509 |
1 files changed, 509 insertions, 0 deletions
diff --git a/src/json.c b/src/json.c new file mode 100644 index 000000000..7b67994dd --- /dev/null +++ b/src/json.c @@ -0,0 +1,509 @@ +/* vi:set ts=8 sts=4 sw=4: + * + * VIM - Vi IMproved by Bram Moolenaar + * + * Do ":help uganda" in Vim to read copying and usage conditions. + * Do ":help credits" in Vim to see a list of people who contributed. + * See README.txt for an overview of the Vim source code. + */ + +/* + * json.c: Encoding and decoding JSON. + * + * Follows this standard: http://www.ietf.org/rfc/rfc4627.txt + */ + +#include "vim.h" + +#if defined(FEAT_EVAL) || defined(PROTO) +static void json_decode_item(js_read_T *reader, typval_T *res); + +/* + * Encode "val" into a JSON format string. + */ + char_u * +json_encode(typval_T *val) +{ + garray_T ga; + + /* Store bytes in the growarray. */ + ga_init2(&ga, 1, 4000); + json_encode_item(&ga, val, get_copyID()); + return ga.ga_data; +} + + static void +write_string(garray_T *gap, char_u *str) +{ + char_u *res = str; + char_u numbuf[NUMBUFLEN]; + + if (res == NULL) + ga_concat(gap, (char_u *)"null"); + else + { + ga_append(gap, '"'); + while (*res != NUL) + { + int c = PTR2CHAR(res); + + switch (c) + { + case 0x08: + ga_append(gap, '\\'); ga_append(gap, 'b'); break; + case 0x09: + ga_append(gap, '\\'); ga_append(gap, 't'); break; + case 0x0a: + ga_append(gap, '\\'); ga_append(gap, 'n'); break; + case 0x0c: + ga_append(gap, '\\'); ga_append(gap, 'f'); break; + case 0x0d: + ga_append(gap, '\\'); ga_append(gap, 'r'); break; + case 0x22: /* " */ + case 0x5c: /* \ */ + ga_append(gap, '\\'); + ga_append(gap, c); + break; + default: + if (c >= 0x20) + { + numbuf[mb_char2bytes(c, numbuf)] = NUL; + ga_concat(gap, numbuf); + } + else + { + vim_snprintf((char *)numbuf, NUMBUFLEN, + "\\u%04lx", (long)c); + ga_concat(gap, numbuf); + } + } + mb_cptr_adv(res); + } + ga_append(gap, '"'); + } +} + + void +json_encode_item(garray_T *gap, typval_T *val, int copyID) +{ + char_u numbuf[NUMBUFLEN]; + char_u *res; + list_T *l; + dict_T *d; + + switch (val->v_type) + { + case VAR_SPECIAL: + switch(val->vval.v_number) + { + case VVAL_FALSE: ga_concat(gap, (char_u *)"false"); break; + case VVAL_TRUE: ga_concat(gap, (char_u *)"true"); break; + case VVAL_NONE: break; + case VVAL_NULL: ga_concat(gap, (char_u *)"null"); break; + } + break; + + case VAR_NUMBER: + vim_snprintf((char *)numbuf, NUMBUFLEN, "%ld", + (long)val->vval.v_number); + ga_concat(gap, numbuf); + break; + + case VAR_STRING: + res = val->vval.v_string; + write_string(gap, res); + break; + + case VAR_FUNC: + /* no JSON equivalent, skip */ + break; + + case VAR_LIST: + l = val->vval.v_list; + if (l == NULL) + ga_concat(gap, (char_u *)"null"); + else + { + if (l->lv_copyID == copyID) + ga_concat(gap, (char_u *)"[]"); + else + { + listitem_T *li; + + l->lv_copyID = copyID; + ga_append(gap, '['); + for (li = l->lv_first; li != NULL && !got_int; ) + { + json_encode_item(gap, &li->li_tv, copyID); + li = li->li_next; + if (li != NULL) + ga_append(gap, ','); + } + ga_append(gap, ']'); + } + } + break; + + case VAR_DICT: + d = val->vval.v_dict; + if (d == NULL) + ga_concat(gap, (char_u *)"null"); + else + { + if (d->dv_copyID == copyID) + ga_concat(gap, (char_u *)"{}"); + else + { + int first = TRUE; + int todo = (int)d->dv_hashtab.ht_used; + hashitem_T *hi; + + d->dv_copyID = copyID; + ga_append(gap, '{'); + + for (hi = d->dv_hashtab.ht_array; todo > 0 && !got_int; + ++hi) + if (!HASHITEM_EMPTY(hi)) + { + --todo; + if (first) + first = FALSE; + else + ga_append(gap, ','); + write_string(gap, hi->hi_key); + ga_append(gap, ':'); + json_encode_item(gap, &dict_lookup(hi)->di_tv, + copyID); + } + ga_append(gap, '}'); + } + } + break; + +#ifdef FEAT_FLOAT + case VAR_FLOAT: + vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", val->vval.v_float); + ga_concat(gap, numbuf); + break; +#endif + default: EMSG2(_(e_intern2), "json_encode_item()"); break; + } +} + +/* + * Skip white space in "reader". + */ + static void +json_skip_white(js_read_T *reader) +{ + int c; + + while ((c = reader->js_buf[reader->js_used]) == ' ' + || c == TAB || c == NL || c == CAR) + ++reader->js_used; +} + +/* + * Make sure there are at least enough characters buffered to read a number. + */ + static void +json_fill_buffer(js_read_T *reader UNUSED) +{ + /* TODO */ +} + + static void +json_decode_array(js_read_T *reader, typval_T *res) +{ + char_u *p; + typval_T item; + listitem_T *li; + + if (rettv_list_alloc(res) == FAIL) + goto fail; + ++reader->js_used; /* consume the '[' */ + + while (TRUE) + { + json_skip_white(reader); + p = reader->js_buf + reader->js_used; + if (*p == NUL) + goto fail; + if (*p == ']') + { + ++reader->js_used; /* consume the ']' */ + return; + } + + if (!reader->js_eof && (int)(reader->js_end - p) < NUMBUFLEN) + json_fill_buffer(reader); + + json_decode_item(reader, &item); + li = listitem_alloc(); + if (li == NULL) + return; + li->li_tv = item; + list_append(res->vval.v_list, li); + + json_skip_white(reader); + p = reader->js_buf + reader->js_used; + if (*p == ',') + ++reader->js_used; + else if (*p != ']') + goto fail; + } +fail: + res->v_type = VAR_SPECIAL; + res->vval.v_number = VVAL_NONE; +} + + static void +json_decode_object(js_read_T *reader, typval_T *res) +{ + char_u *p; + typval_T tvkey; + typval_T item; + dictitem_T *di; + char_u buf[NUMBUFLEN]; + char_u *key; + + if (rettv_dict_alloc(res) == FAIL) + goto fail; + ++reader->js_used; /* consume the '{' */ + + while (TRUE) + { + json_skip_white(reader); + p = reader->js_buf + reader->js_used; + if (*p == NUL) + goto fail; + if (*p == '}') + { + ++reader->js_used; /* consume the '}' */ + return; + } + + if (!reader->js_eof && (int)(reader->js_end - p) < NUMBUFLEN) + json_fill_buffer(reader); + json_decode_item(reader, &tvkey); + key = get_tv_string_buf_chk(&tvkey, buf); + if (key == NULL || *key == NUL) + { + /* "key" is NULL when get_tv_string_buf_chk() gave an errmsg */ + if (key != NULL) + EMSG(_(e_emptykey)); + clear_tv(&tvkey); + goto fail; + } + + json_skip_white(reader); + p = reader->js_buf + reader->js_used; + if (*p != ':') + { + clear_tv(&tvkey); + goto fail; + } + ++reader->js_used; + json_skip_white(reader); + + if (!reader->js_eof && (int)(reader->js_end - p) < NUMBUFLEN) + json_fill_buffer(reader); + json_decode_item(reader, &item); + + di = dictitem_alloc(key); + clear_tv(&tvkey); + if (di == NULL) + { + clear_tv(&item); + goto fail; + } + di->di_tv = item; + dict_add(res->vval.v_dict, di); + + json_skip_white(reader); + p = reader->js_buf + reader->js_used; + if (*p == ',') + ++reader->js_used; + else if (*p != '}') + goto fail; + } +fail: + res->v_type = VAR_SPECIAL; + res->vval.v_number = VVAL_NONE; +} + + static void +json_decode_string(js_read_T *reader, typval_T *res) +{ + garray_T ga; + int len; + char_u *p = reader->js_buf + reader->js_used + 1; + int c; + long nr; + char_u buf[NUMBUFLEN]; + + ga_init2(&ga, 1, 200); + + /* TODO: fill buffer when needed. */ + while (*p != NUL && *p != '"') + { + if (*p == '\\') + { + c = -1; + switch (p[1]) + { + case 'b': c = BS; break; + case 't': c = TAB; break; + case 'n': c = NL; break; + case 'f': c = FF; break; + case 'r': c = CAR; break; + case 'u': + vim_str2nr(p + 2, NULL, &len, + STR2NR_HEX + STR2NR_FORCE, &nr, NULL, 4); + p += len + 2; +#ifdef FEAT_MBYTE + buf[(*mb_char2bytes)((int)nr, buf)] = NUL; + ga_concat(&ga, buf); +#else + ga_append(&ga, nr); +#endif + break; + default: c = p[1]; break; + } + if (c > 0) + { + p += 2; + ga_append(&ga, c); + } + } + else + { + len = MB_PTR2LEN(p); + if (ga_grow(&ga, len) == OK) + { + mch_memmove((char *)ga.ga_data + ga.ga_len, p, (size_t)len); + ga.ga_len += len; + } + p += len; + } + if (!reader->js_eof && (int)(reader->js_end - p) < NUMBUFLEN) + { + reader->js_used = (int)(p - reader->js_buf); + json_fill_buffer(reader); + p = reader->js_buf + reader->js_used; + } + } + reader->js_used = (int)(p - reader->js_buf); + if (*p == '"') + { + ++reader->js_used; + res->v_type = VAR_STRING; + res->vval.v_string = vim_strsave(ga.ga_data); + } + else + { + res->v_type = VAR_SPECIAL; + res->vval.v_number = VVAL_NONE; + } + ga_clear(&ga); +} + +/* + * Decode one item and put it in "result". + * Must already have skipped white space. + */ + static void +json_decode_item(js_read_T *reader, typval_T *res) +{ + char_u *p = reader->js_buf + reader->js_used; + + switch (*p) + { + case '[': /* array */ + json_decode_array(reader, res); + return; + + case '{': /* object */ + json_decode_object(reader, res); + return; + + case '"': /* string */ + json_decode_string(reader, res); + return; + + case ',': /* comma: empty item */ + case NUL: /* empty */ + res->v_type = VAR_SPECIAL; + res->vval.v_number = VVAL_NONE; + return; + + default: + if (VIM_ISDIGIT(*p) || *p == '-') + { + int len; + char_u *sp = p; +#ifdef FEAT_FLOAT + if (*sp == '-') + ++sp; + sp = skipdigits(sp); + if (*sp == '.' || *sp == 'e' || *sp == 'E') + { + res->v_type = VAR_FLOAT; + len = string2float(p, &res->vval.v_float); + } + else +#endif + { + long nr; + + res->v_type = VAR_NUMBER; + vim_str2nr(reader->js_buf + reader->js_used, + NULL, &len, 0, /* what */ + &nr, NULL, 0); + res->vval.v_number = nr; + } + reader->js_used += len; + return; + } + if (STRNICMP((char *)p, "false", 5) == 0) + { + reader->js_used += 5; + res->v_type = VAR_SPECIAL; + res->vval.v_number = VVAL_FALSE; + return; + } + if (STRNICMP((char *)p, "true", 4) == 0) + { + reader->js_used += 4; + res->v_type = VAR_SPECIAL; + res->vval.v_number = VVAL_TRUE; + return; + } + if (STRNICMP((char *)p, "null", 4) == 0) + { + reader->js_used += 4; + res->v_type = VAR_SPECIAL; + res->vval.v_number = VVAL_NULL; + return; + } + break; + } + + EMSG(_(e_invarg)); + res->v_type = VAR_SPECIAL; + res->vval.v_number = VVAL_NONE; +} + +/* + * Decode the JSON from "reader" and store the result in "res". + */ + void +json_decode(js_read_T *reader, typval_T *res) +{ + json_skip_white(reader); + json_decode_item(reader, res); + json_skip_white(reader); + if (reader->js_buf[reader->js_used] != NUL) + EMSG(_(e_invarg)); +} +#endif |