revised example

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CK Tan 2020-12-05 14:19:53 -08:00
parent a2d704c7af
commit ae9514e87b
3 changed files with 97 additions and 84 deletions

118
README.md
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@ -4,6 +4,13 @@ TOML in c99; v1.0 compliant.
If you are looking for a C++ library, you might try this wrapper: [https://github.com/cktan/tomlcpp](https://github.com/cktan/tomlcpp). If you are looking for a C++ library, you might try this wrapper: [https://github.com/cktan/tomlcpp](https://github.com/cktan/tomlcpp).
* Compatible with [TOML v1.0.0-rc.3](https://toml.io/en/v1.0.0-rc.3).
* Tested with multiple test suites, including
[BurntSushi/toml-test](https://github.com/BurntSushi/toml-test) and
[iarna/toml-spec-tests](https://github.com/iarna/toml-spec-tests).
* Provides very simple and intuitive interface.
## Usage ## Usage
Please see the `toml.h` file for details. What follows is a simple example that Please see the `toml.h` file for details. What follows is a simple example that
@ -12,84 +19,81 @@ parses this config file:
```toml ```toml
[server] [server]
host = "www.example.com" host = "www.example.com"
port = 80 port = [ 8080, 8181, 8282 ]
``` ```
The steps for getting values from our file is usually : The steps for getting values from our file is usually :
1. Parse the whole TOML file. 1. Parse the TOML file.
2. Get a single table from the file. 2. Traverse to a table.
3. Find a value from the table. 3. Extract values from the table.
4. Then, free up that memory if needed. 4. Then, free up that memory if needed.
Below is an example of parsing the values from the example table. Below is an example of parsing the values from the example table.
1. Parse the whole TOML file.
```c ```c
FILE* fp; #include <stdio.h>
toml_table_t* conf; #include <string.h>
char errbuf[200]; #include <errno.h>
#include <stdlib.h>
#include "toml.h"
/* Open the file and parse content */ static void fatal(const char* msg, const char* msg1)
if (0 == (fp = fopen("path/to/file.toml", "r"))) { {
return handle_error(); fprintf(stderr, "ERROR: %s%s\n", msg, msg1?msg1:"");
} exit(1);
conf = toml_parse_file(fp, errbuf, sizeof(errbuf));
fclose(fp);
if (0 == conf) {
return handle_error();
} }
/* Alternatively, use `toml_parse` which takes a string rather than a file. */ int main()
conf = toml_parse("A null terminated string that is TOML\0", errbuf, sizeof(errbuf)); {
``` FILE* fp;
char errbuf[200];
2. Get a single table from the file. // 1. Read and parse toml file
fp = fopen("sample.toml", "r");
if (!fp) {
fatal("cannot open sample.toml - ", strerror(errno));
}
```c toml_table_t* conf = toml_parse_file(fp, errbuf, sizeof(errbuf));
toml_table_t* server; fclose(fp);
/* Locate the [server] table. */ if (!conf) {
if (0 == (server = toml_table_in(conf, "server"))) { fatal("cannot parse - ", errbuf);
return handle_error(); }
}
```
3. Find a value from the table. // 2. Traverse to a table.
toml_table_t* server = toml_table_in(conf, "server");
if (!server) {
fatal("missing [server]", "");
}
```c // 3. Extract values
/* Extract 'host' config value. */ toml_datum_t host = toml_string_in(server, "host");
toml_datum_t host = toml_string_in(server, "host"); if (!host.ok) {
if (!host.ok) { fatal("cannot read server.host", "");
toml_free(conf); }
return handle_error();
}
toml_datum_t port = toml_int_in(server, "port"); toml_array_t* portarray = toml_array_in(server, "port");
if (!port.ok) { if (!portarray) {
toml_free(conf); fatal("cannot read server.port", "");
}
printf("host: %s\n", host.u.s);
printf("port: ");
for (int i = 0; ; i++) {
toml_datum_t port = toml_int_at(portarray, i);
if (!port.ok) break;
printf("%d ", (int)port.u.i);
}
printf("\n");
// 4. Free memory
free(host.u.s); free(host.u.s);
return handle_error(); toml_free(conf);
return 0;
} }
printf("host %s\n", host.u.s);
printf("port %d\n", port.u.i);
```
4. Then, free up that memory if needed.
```c
/* Use `toml_free` on the table returned from `toml_parse[_file]`.
* NOTE: you only need to `toml_free` the root table returned by `toml_parse[_file]`;
* internal tables do not need to be freed.
*/
toml_free(conf);
/* Free any string values returned from access functions. */
free(host.u.s);
``` ```
#### Accessing Table Content #### Accessing Table Content

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@ -1,3 +1,3 @@
[server] [server]
host = "example.com" host = "example.com"
port = 80 port = [ 8080, 8181, 8282 ]

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@ -4,49 +4,58 @@
#include <stdlib.h> #include <stdlib.h>
#include "toml.h" #include "toml.h"
toml_table_t* load() static void fatal(const char* msg, const char* msg1)
{
fprintf(stderr, "ERROR: %s%s\n", msg, msg1?msg1:"");
exit(1);
}
int main()
{ {
FILE* fp; FILE* fp;
char errbuf[200]; char errbuf[200];
// 1. Read and parse toml file
fp = fopen("sample.toml", "r"); fp = fopen("sample.toml", "r");
if (!fp) { if (!fp) {
fprintf(stderr, "ERROR: cannot open sample.toml - %s\n", strerror(errno)); fatal("cannot open sample.toml - ", strerror(errno));
exit(1);
} }
toml_table_t* conf = toml_parse_file(fp, errbuf, sizeof(errbuf)); toml_table_t* conf = toml_parse_file(fp, errbuf, sizeof(errbuf));
fclose(fp); fclose(fp);
if (!conf) { if (!conf) {
fprintf(stderr, "ERROR: cannot parse - %s\n", errbuf); fatal("cannot parse - ", errbuf);
exit(1);
} }
return conf;
}
int main() // 2. Traverse to a table.
{
toml_table_t* conf = load();
toml_table_t* server = toml_table_in(conf, "server"); toml_table_t* server = toml_table_in(conf, "server");
if (!server) { if (!server) {
fprintf(stderr, "ERROR: missing [server]\n"); fatal("missing [server]", "");
exit(1);
}
toml_datum_t host = toml_string_in(server, "host");
if (!host.ok) {
fprintf(stderr, "ERROR: cannot read server.host.\n");
exit(1);
}
toml_datum_t port = toml_int_in(server, "port");
if (!port.ok) {
fprintf(stderr, "ERROR: cannot read server.port.\n");
exit(1);
} }
printf("host: %s, port %d\n", host.u.s, (int)port.u.i); // 3. Extract values
toml_datum_t host = toml_string_in(server, "host");
if (!host.ok) {
fatal("cannot read server.host", "");
}
toml_array_t* portarray = toml_array_in(server, "port");
if (!portarray) {
fatal("cannot read server.port", "");
}
printf("host: %s\n", host.u.s);
printf("port: ");
for (int i = 0; ; i++) {
toml_datum_t port = toml_int_at(portarray, i);
if (!port.ok) break;
printf("%d ", (int)port.u.i);
}
printf("\n");
// 4. Free memory
free(host.u.s); free(host.u.s);
toml_free(conf); toml_free(conf);
return 0; return 0;