comparison: dbd/postgresql/statement.c
dbd/postgresql/statement.c
- changeset 17
- 21c4feaeafe7
- parent 12
- 014ba3ab3903
- child 20
- 5ab0b30f8fbd
equal
deleted
inserted
replaced
| 16:318e5dfd03b8 | 17:21c4feaeafe7 |
|---|---|
| 1 #include "dbd_postgresql.h" | 1 #include "dbd_postgresql.h" |
| 2 | |
| 3 #define MAX_PLACEHOLDERS 9999 | |
| 4 #define MAX_PLACEHOLDER_SIZE (1+4) /* $\d{4} */ | |
| 5 | 2 |
| 6 static lua_push_type_t postgresql_to_lua_push(unsigned int postgresql_type) { | 3 static lua_push_type_t postgresql_to_lua_push(unsigned int postgresql_type) { |
| 7 lua_push_type_t lua_type; | 4 lua_push_type_t lua_type; |
| 8 | 5 |
| 9 switch(postgresql_type) { | 6 switch(postgresql_type) { |
| 26 } | 23 } |
| 27 | 24 |
| 28 return lua_type; | 25 return lua_type; |
| 29 } | 26 } |
| 30 | 27 |
| 31 /* | |
| 32 * replace '?' placeholders with $\d+ placeholders | |
| 33 * to be compatible with PSQL API | |
| 34 */ | |
| 35 static char *replace_placeholders(lua_State *L, const char *sql) { | |
| 36 size_t len = strlen(sql); | |
| 37 int num_placeholders = 0; | |
| 38 int extra_space = 0; | |
| 39 int i; | |
| 40 char *newsql; | |
| 41 int newpos = 1; | |
| 42 int ph_num = 1; | |
| 43 int in_quote = 0; | |
| 44 | |
| 45 /* | |
| 46 * dumb count of all '?' | |
| 47 * this will match more placeholders than necessesary | |
| 48 * but it's safer to allocate more placeholders at the | |
| 49 * cost of a few bytes than risk a buffer overflow | |
| 50 */ | |
| 51 for (i = 1; i < len; i++) { | |
| 52 if (sql[i] == '?') { | |
| 53 num_placeholders++; | |
| 54 } | |
| 55 } | |
| 56 | |
| 57 /* | |
| 58 * this is MAX_PLACEHOLDER_SIZE-1 because the '?' is | |
| 59 * replaced with '$' | |
| 60 */ | |
| 61 extra_space = num_placeholders * (MAX_PLACEHOLDER_SIZE-1); | |
| 62 | |
| 63 /* | |
| 64 * allocate a new string for the converted SQL statement | |
| 65 */ | |
| 66 newsql = malloc(sizeof(char) * (len+extra_space+1)); | |
| 67 memset(newsql, 0, sizeof(char) * (len+extra_space+1)); | |
| 68 | |
| 69 /* | |
| 70 * copy first char. In valid SQL this cannot be a placeholder | |
| 71 */ | |
| 72 newsql[0] = sql[0]; | |
| 73 | |
| 74 /* | |
| 75 * only replace '?' not in a single quoted string | |
| 76 */ | |
| 77 for (i = 1; i < len; i++) { | |
| 78 /* | |
| 79 * don't change the quote flag if the ''' is preceded | |
| 80 * bt a '\' to account for escaping | |
| 81 */ | |
| 82 if (sql[i] == '\'' && sql[i-1] != '\\') { | |
| 83 in_quote = !in_quote; | |
| 84 } | |
| 85 | |
| 86 if (sql[i] == '?' && !in_quote) { | |
| 87 size_t n; | |
| 88 | |
| 89 if (ph_num > MAX_PLACEHOLDERS) { | |
| 90 luaL_error(L, "Sorry, you are using more than %d placeholders. Use ${num} format instead", MAX_PLACEHOLDERS); | |
| 91 } | |
| 92 | |
| 93 n = snprintf(&newsql[newpos], MAX_PLACEHOLDER_SIZE, "$%u", ph_num++); | |
| 94 | |
| 95 newpos += n; | |
| 96 } else { | |
| 97 newsql[newpos] = sql[i]; | |
| 98 newpos++; | |
| 99 } | |
| 100 } | |
| 101 | |
| 102 /* | |
| 103 * terminate string on the last position | |
| 104 */ | |
| 105 newsql[newpos] = '\0'; | |
| 106 | |
| 107 /* fprintf(stderr, "[%s]\n", newsql); */ | |
| 108 return newsql; | |
| 109 } | |
| 110 | 28 |
| 111 /* | 29 /* |
| 112 * success = statement:close() | 30 * success = statement:close() |
| 113 */ | 31 */ |
| 114 static int statement_close(lua_State *L) { | 32 static int statement_close(lua_State *L) { |
| 357 char name[IDLEN]; | 275 char name[IDLEN]; |
| 358 | 276 |
| 359 /* | 277 /* |
| 360 * convert SQL string into a PSQL API compatible SQL statement | 278 * convert SQL string into a PSQL API compatible SQL statement |
| 361 */ | 279 */ |
| 362 new_sql = replace_placeholders(L, sql_query); | 280 new_sql = replace_placeholders(L, '$', sql_query); |
| 363 | 281 |
| 364 snprintf(name, IDLEN, "%017u", ++conn->statement_id); | 282 snprintf(name, IDLEN, "%017u", ++conn->statement_id); |
| 365 | 283 |
| 366 result = PQprepare(conn->postgresql, name, new_sql, 0, NULL); | 284 result = PQprepare(conn->postgresql, name, new_sql, 0, NULL); |
| 367 | 285 |
